USING "CASE STUDY" AND "COOPERATIVE LEARNING"
T'XACtruuG APPROACHES IN A SECOND-YEAR
PHYSl[OLOGY COURSE AT DALAT UNIVERSITY
Doan Thi My
B-Sc., University of Ho Chi Minh City, 198 1
THESIS SUBMITIED IN PARTIAL FULFILLMENT OF
THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF SCIENCE
in the Faculty
of
Education
O Doan Thi My 1996
SIMON FRASER UNIVERSITY
April 1996
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Title of Thesis/Project/Extended Essay
Using "Case Study" and "Cooperative-Learning" Teaching Approaches in
a Second-Year Physiology Course at Dalat University
(Signature)
APPROVAL
NAME My Doan Thi
DEGREE Master of Science
TITLE Using "Case Study" and "Cooperative-Learning" teaching Approaches in a Second-Year Physioio~y Course at Dalat University
Chair Michael Manley-Casimir
Allan MacKinnon, Assistant Professor Senior Supervisor
Marvin Wideen, Professor Member
Dr. Celia Haig-Brown, Faculty of Education, SFU External Examiner
Abstract
The "teacher-centered" method, which is common in Vietnamese schools and
universities, pays little attention to students' developing cognitive and problem solving
abilities in science, their self-confidence as learners and their skills in communication,
working with others, critical thinking, and self-appraisal. There is a need for "student-
centered" teaching methods in Vietnamese schools. This study investigated a "case
method" of teaching in a second-year physiology course, with whole-class discussions
and cooperative group work.
Taking place at Dalat University in Viernam in the fall of 1995, the study involved
a qualitative analysis of three sections of 42 students enrolled in the physiology course,
focusing on students' perspectives about school, students' attitudes toward the "trial"
methods of teaching and learning, and the feasibility of applying the new teaching
approaches on a broader scale.
Data were coliected from 3 main sources: (1) a survey, (2) a course evaluation, a
self-evaluation and midterm examination, and (3) observations and a group interview with
6 students. The survey data are analyzed mainly by descriptive interpretation and partly
by quantitative analysis. Main themes from the transcripts of the observations and
interview are coded and analyzed by in terms of the focused research problems.
Findings from the study show that the students had highly positive attitudes
toward school; they had a keen concern about the content and teaching methods in
biology courses, about the need of social skill development. The new teaching
approaches were reported to be useful in developing deeper understandings of science,
and other skills such as oral communication, trust building, and self-confidence. Among
the conclusions is a set of recommendations and limitations of the study.
Dedication
This work is dedicated to the Canadian International Development
Agency, Simon Fraser University, Dalat University, and the Department
of Biology at Dalat University; the Department Head and all my
colleagues, students of the third and fourth year , especially students from
the second year part-time program of Dalat University who participated
in experiencing the new approaches. Thank you for your inspiration and
commitment.
Acknowledgements
I am indebted to Ms. Sandra Sachs, Dr. Bruce Clayman, Dr
Thomas O'Shea, Dr. Allan MacKinnon who provided me a great
opportunity to study in Canada.
Special acknowledgment goes to Dr. Allan MacKinnon, Dr.
Marvin Wideen, and Dr. Celia Haig-Brown for their valued instructions,
comments and assistance with this study. I am also grateful to Susan
Gerofsky and her husband Phil Byrne, "Editors-in-Chief ', for their great
support in editing the thesis.
Last, bu: not least, I acknowledge my parents, and my husband
Jinryo Takiialii, whose support and encouragement kept me going. And
to my darling daughter, My Thao, who offered her childhood living far
away from mom and seemed to have a greL! patience in waiting for me to
come back. Thank you.
Table of Contents
Page
. . .................................................................................................................. Approval 11
... .................................................................................................................... Abstract 111
. . ................................................................................................................ Dedication iv
.................................................................................................... Acknowledgments v
Chapter 1 . Background and Statement of the Problem ..................................... 1
Social context ............... .. ............................................................................ 1
Dalat University context ............................................................................... 6
The need for the study .................................................................................. 9
Statement of research problem ..................................................................... 9 . .
Organlzatlon of the Thesis .......................................................................... 10
Chapter 2 . A Review of Related Literature ...................................................... 11
Cooperative learning ................................................................................ 11
How to teach Cooperative Learning ............................................... 14
Cooperative Learning group methods in teaching biology .............. 20
Case Study ................................................................................................... 20
History, development and significant meanings .............................. 20
Case study in biology with Cooperative Learning in groups ........... 24
Critics of case study method ........................................................................ 27
Chapter 3 . Research Methods .............................................................................. 29
. . Descnpbon of the study ............................................................................... 29
............................................................................................. The preparation 31
vii
......................................................................... Survey questionnaire 31
7 Case study ........................................................................................ 3&
.................................................................... The physiology course - 3 3 . . ............................................................................. Application of the study 34
............................................. Background survey with consent form 34
.......................................................... Feedback from the pilot study 34
.............................................................................. Doing the survey -35
Teaching with "student-centered" methods ...................................... 36
Teaching with case study: the "Pig Bel" ........................................... 42
66 77 ........................................................................... Play stage 42
66 . 7 9 ...................................................................... Debnet stage 43
c i 9 9 ....................................................................... Replay stage 43
Course evaluation .............................................................................. 45
........................................ Self-evaluation and midterm examination 45
......................................................................... Data coilection and analysis 46
The survey ........................................................................................ 46
.................................................................................... Observations A7
......................................................... Whole-class discussion 48
Case study discussion ........................................................... 49
.............................. Self-evaluation and midterm examination result 50
.............................................................................. Course evaluation 50
........................................................................................... Interview 50
. . ............................................................................... Internal vahdity -52
........................................................................................ Reliability -53 . . .............................................................................. External valid^ ty -54
viii
......................................................................... Chapter 4 . Findings of the Satdy S5
................................................................................... Background survey -55
........................................................................................... ............. Survey i. -56
................................................................................................ Observations -64
..................................................................... Whole-class discussion 64
................................... Memorization-dominated discussion -64
Conflict and conflict management ........................................ 67
................................................. Male-dominated discussion -68
....................................................................... Case study discussion 69
.............................................. Female-dominated discussion -69
Seeking more information from other materials ................... 70
............................... Reasoning skill and deep understanding 73
Cooperative group work and individual accountability ....... 76
....................................................................................................... Interview 80
......................................... Students' impressions of the approaches -80
Socid skill focus ............................................................................... 81
Deep understaxidkg about the course .............................................. -82
............................................................ Teacher-student relationship 84
Suggestions for improvements in the content
of physiology course ........................................................................ 86
...................................................... Course evaluation ........................... .. 3 7
..................................................................................... Good points -88
....................................................................................... Drawbacks -88
......................................... SeIf-evduation md midterm examination result -89
. . Midterm exammatlon ....................................................................... -89
Chapter 5 . Conclusions, Limitations and Recommendations ............................ 91
From research question to research results ................................................... 91
................................................................................................... Conclusions 94
...................................................... From research results to generalizability 95
.......................................... Limited funds for the course preparation 95
................................... Lack of concern from colleagues and faculty 96
................... Lack of patience or tolerance for unexpected situations 96
........................................ Preparation of course and other materials 97
Flexibility in instruction methods ..................................................... 98 . . .
Lirmtations of the research ............................................................................ 98
................................................................ Recommendations for application 99 . .
Bibhography ......................................................................................................... 101
......................... Appendix A - Survey of Students' Perspectives Toward School 105
Appendix B - Interview Questions ........................................................................ 107
66 . Appendix C - The Pg-Bel" .................................................................................. 109
Appendix D - Group Observations ........................................................................ 127
Appendix E - Background Survey with Consent Form ........................................ 140
Appendix F - Course Evaluation ........................................................................... 145
Appendix G - Self-Evaluation ............................................................................... -146
Appendix H - Midterm Examination Questions ................................................... -147
. List of Tables
Page
................................................ Table I . Agreement percentage of statement One -56
................................................ Table 2 . Agreement percentage of statement Two 57
.............................................. Table 3 . Agreement percentage of statement Three 57
Table 4 . Agreement percentage of statement Four ............................................... 58
Table 5 . Agreement percentage of statement Five ................................................. 58
................................................... Table 6 . Agreement percentage of statement Six 59
.............................................. Table 7 . Agreement percentage of statement Seven 59
............................................... Table 8 . Agreement percentage of statement Eight 60
................................................ Table 9 . Agreement percentage of statement Nine 61
Table 10 . Agreement percentage of statement Ten .............................................. -61
Table 1 1 . ANOVA summary table for comparison
of different averaged marks of the three populations .......................... 03
Table 12 . Male-dominated discussion .................................................................. 69
Table 13 . Female-dominated discussion ................................................................ 70
Chapter One
Background and Statement of the Problem
Social context
Following the unificadm of Vietnam in 1975, massive changes have occurred in
the country's educational system. In 1990, the former Ministry of Education, the General
Department for Vocational Training, and the Miniqtry of Higher and Secondary Technical
Education were fussed together as one Ministry of Education and Training. The first five
years after reunification were also marked by a severe shortage of well qualified people in
the general wotkfcrce, poor economic conditions, and very few resources for educational
purposes. The government has undertaken enormous efforts to alleviate illiteracy, yet
there remain some persistent problems in the remote mountain areas m d in the Mekong
Delta area, where there are inadequate schools and a shortage of teachers.
The Educational system in Vietnam has been organized into two levels of
administration: the cenirally-based administration for the country as a whole, and the
locally-based provincial administration. Both of these belong to the Ministry of
Education. All universities are directly administered by the Central Ministry, while
kindergarten, elementary, secondxy and high schools are administered by the General
Department of Education in each province (Duiker, 1987).
In addition to the public school system, Vietnam still has the serni-publ ic schools
for students who did not take or pass the entrance exams for basic education level 2 (from
grade 5 to grade 61, or for secondary sch001 (from grade 9 to grade I@, The semi-public
schools include evening schools for students who work during the day and vocational
schoots for those who intend to obtain specialized skills.
In higher education, the Vietnamese use a system of competitive examinations to
select university students. Only talose students who have passed the "School Leaving
Examination" are allowed to take the university entrance exam. If they pass the
university entrance examination, which is administered by the individual universities,
their tuition of the first semester is provided by the government. Scholarships and modest
iiving afiowances are awarded in the second semester of the first year for high
priornarrce students (A avemge). In an attempt to further open fhe university system,
however, the Ministry has also decided to admit additional students on a tuition-paying
basis. Thus, there are two training systems in Vietnamese uriiversities: the "regular" and
the "open" sections. But while students are kept in separate classes, they are taught the
same curriculum. One of the effects of the "open door policy," then, is a greater variety in
students' background, aptitude, and basic knowledge.
Before 1990, all schocrls of the country, except for university, had the same
curriculum, created and revised by the Curriculum Revision Committee of the Ministry of
Education. Each of the universities has its own curriculum for teaching and learning
based on its own purposes, contexts, and culture appropriate to the goals of national
education (Duiker, 1987).
- I ne natictnai incentive to upgrade the educational system, however, led to the
development of a plan in 1990 to restructure post-secondary science education in
Vietnam. A consortium of eleven universities was formed to undertake the incumbent
science curriculum development and teacher education. The broad intention of this plan
was to establish a "University Credit System." which includes two phases of work for
undergraduate students of science. The first phase is a "Basic Science" component which
will be eventually taught in community colleges across the country. The university
system of the first phase was divided into seven subject groups (Curriculum
Development, Ministry of Education and Training, 1992) : Mathematics; Physics:
Chemistry; Biology-Medicine-Agriculture; Economics; Humanities and Science; and
Social Science. After two years of study in this basic science program, students will
transfer in to university fur the second phase of their education; the science specialization
(fisheries, agriculture, engineering, etc.). This University Credit System will thus enable
improved access to a basic science education, particularly in the remote areas of the
country, and a solid foundation for further study of science in applied contexts.
While the broad purpose for this restructuring is to increase access to basic science
education, and, therefore, to improve the scientific and technological literacy of the
Vietnamese citizenry, there are many problems and conditions that help to shape the
specific nature of the impending reform. The country has been somewhat isolated from
the professional science and science education communities of the past twenty years, and
textbooks and teaching methods reflecting current understandings in science are lacking.
The curriculum has been focused almost exclusively on the study of theoretical and
classical subjects, particuiady Vietnamese iiterature (primarily classical and war
literature) and mathematics, and, in spite of a policy emphasis to the contrary, has tended
to under-emphasize practical experimentation and technical competencies for future
careers. In addition to these problems, the condition of teaching laboratories is very poor
in a certain areas of the country, and this, in part, has led to a rather "rhetorical" science
education, that is, one which relies heavily on rote memorization and routinization, at the
expense of a "broad and deep understanding" of the subject matter which reflects the
fundamental principles of science. The need to learn by memorization is exacerbated by
the lack of practical, concrete laboratory activities that are relevant and motivating for
students.
Under the open door policy, especially since the lifting of the United States
embargo, the government is making a great attempt to rebuild the new educationai system
at all levels to meet the needs of a country which is developing eagerly and rapidly after
several decades of war. There is a renewed spirit in Vietnam for curriculum development,
and school and university curriculum revision has been undertaken at an unprecedented
rate. For those unfamiliar with the historical and political context of Vietnam, it is
difficult to imagine the impetus lying behind these recent developmental incentives.
Vietnam is now almost independent from external political control, and the
cc*ntry has arisen to voice ambitious development goals envisioning a renewed emphasis
on its own national history and character, a new socio-economic structure, universal
education, and broad scale welfare measures. Much of the burden for bringing such goals
to reality has fallen upon the schools, and, clearly, if the schools are to carry out their
charge, they must effect widespread curriculum changes (Duiker, 1987). The open door
policy has been accompanied by a rhetoric that portrays a vast amount of information
available to the scientific and literary world. We are told of an explosion in
information-a doubling each fifteen years or so. This rhetoric further stimulates
curriculum revision.
The rapid growth of the nation's population is yet another factor related to the
historical and political context of the recent educational reforms. The population of
Vietnam is forecast to be 82 million by the year 2000, and there are accompanying visions
of new approaches to administering schools and to teaching large groups. Team teaching,
ability grouping, auto-instructional devices, educational television and teacher-aide
programs are anticipated to help cope with the demands of expanding enrollments
(Beresford, 1988). Such measures and innovations are included in the compulsory
mandate of the government. The new curriculum itself is seen as a measure to help solve
national problems such as birth control, unemployment, health care, etc. Finally, there
have been warnings from Vietnamese and foreign commentators that the old theoretically-
oriented curriculum is not appropriate to the current requirements and, if it were to
become more overloaded with content, would actually reduce the amount of time students
have to pursue their own interest and talents (Duiker, 1987).
One area of increasing knowledge which has had a special impact on the
educational community concerns human learning. The newer ideas about learning and
about individual differences among learners have led to new methods of teaching, such as
inquiry learning, cooperative learning, role play, and many others. Not only is there a
need to develop an appropriate science curriculum and program of studies that reflect the
true nature of the science enterprise, the inter-relations among science, technology and
society, and the historical and philosophical bases for scientific theories and
6
achievements; there is also a need ibr educational reform to fit with the shifting societal
norms and expectations surrounding the role of teachers and schools. With the
Vietnamese institutions of higher education currently changing from a Soviet to an
American design, some of these norms and expectations have already begun to shift. The
problem of fitting in with these shifting norms and expectations is extremely complex,
however, and even when educators and administrators have agreed to move away from
learning by rote insofar as the curriculum design is concerned, there remain reinforcing
influences to rote memorization, such as the competition required for limited
scholarships. Every semester only one-third of the students are admitted to scholarships,
depending on their scores on entrance exams which tend to favour the recitation of
information.
Dalat University context
Dalat university, where this study takes place, is one of the universities which has
attempted to apply the "University Credit System" since 1994. The education training
program has two stages corresponding with Fall, Spring and Summer semesters. The
credit system and grade point average are similar to North America Universities.
Stage I: 3 semesters for 90 credit hours
At high school in grade 10, students choose one of the following specialized
programs:
Program A: mathematics, physics, and chemistry
Program B: biology, mathematics, and chemistry
Program C: mathematics, literature. and geography
Program D: mathematics, history, and foreign kmguage
Depending on the program they finish at high school, students with a High School
Diploma enter the University (after passing the entrance examination) in one of seven
following programs: Mathematics, Physics, Chemistry and Biology, Business
Administration, Vietnamese Studies, History, and English (Training Guide Book of Baht
University, 1995-1996). After this first stage students are granted a General University
Degree. The Department of General Education at the University is responsible for
administering the first stage.
It is important to note that, in an attempt to increase its operating scale, Dalat
University has undertaken an increase in its enrollment from 6000 in 1994 to 8500 in
1995.
Stace 11: 5 semesters for 120 credit hours
Students with excellent performance are eligible to register in courses from any of
three programs in stage 11 directly, without taking a transferring examination. Average or
low performance students must pass an exam to transfer into stage 11.
The administration and organization of stage I1 is managed by each academic
program. Students of stage 11 in the Department of Biology, for instance, are managed by
the Department of Biology itself, not by the Department of General Education. Each
department is also responsible for part-time education.
Dalat University also shares the same problems as the university system as a
whole. Because of a lack of qualified instructors, as mentioned above, the auto-
instructional video-teaching method has now invaded most courses in Stage I. While
Ministry's evaluations have been positive, students complain bitterly. Students attend
school six days a week, and, with few textbooks available, they have to take notes
completely from instructors' lectures. With the teacher-centered method students hardly
have a chance to share their ideas, to acquire a deep understanding about the course, and
to develop other skills such as personal communication, critical reasoning, and so forth.
The University does not require students to attend class, and examinations are considered
to be precise measures of students' performance. Since there are no midterm exams at
Daht University, the end of each semester brings successive final exams for many
courses, which makes this time especially hard for students. Students also have no
opportunity to give their feedback about the courses through course evaluations.
In addition to these problems, university classes in Dalat are characterized by
racial and ability factors. Roughly 10 percent of students use the Vietnamese language
(King) as a second language. These students confront many difficulties in understanding
the materials presented in their courses, in communicating with others, and, often, in
overcoming inferiority complexes associated with their social status. Although the
government has given some special priorities of funding for members of minorities, the
number of native students, who come from rural mountain villages and communities, in
university has not increased since 1975 (Beresford, 1988).
The need for the study
The "direct teaching" method, which is common in Vietnamese schools and
universities, pays little attention to students' developing cognitive and problem-solving
abilities in science, their self-confidence as learners and their skills in communication,
working with others, critical thinking, and self-appraisal. Not only is there a need for
different models of teaching in Vietnam, there is a need for teachers to know which
models are suited for particular purposes, and which combinations of teaching models are
appropriate in certain contexts.
Statement of the research problem
The problem for this thesis is to develop and investigate a physiology course for
second-year university students, emphasizing a repertoire of teaching models appropriate
for the goals of educational and societal reform in Vietnam, as well as the current
conditions surrounding education in the country. Specifically, the thesis addresses
questions of how an intended curriculum is developed, what will be taught, and how it
will be taught and assessed. The focused research problems are as follows:
Do student-centered methods with whole-class and group discussions of STS
content change students' attitudes toward learning science, when they have
been under the strong influence of a teacher-centered tradition?
Does the case study teaching method with cooperative learning in groups bring
about a deep understanding of the course and other related subjects?
Does discussion-based teaching help students develop their social skills?
In order to answer these research questions, on a small and limited scale, this
thesis focuses on the teaching a physiology course to a class of 42 part-time students in
the Department of Biology at Dalat University in Vietnam, in which various "student-
centered" teaching approaches are developed and explored. Specifically, the thesis is an
exploratory, qualitative study of a combination of student-centered methods, including
whole-class discussion surrounding case studies in physiology.
Organization of the Thesis
This is an exploratory stildy of "student-centered" teaching strategies for a basic
science course in Dalat university. The teaching approaches emphasized relationships
between physiology and scientific achievement in solving global problems, focusing on
case study as a means of enabling cooperative learning in groups. Chapter One has
introduced the context of education in Vietnam, the need for the study, and the statement
of the research problems and questions for the study. Chapter Two reviews a litera, +ure on
cooperative learning and the case study method in the teaching of science, focusing
especially on biology and physiology. Chapter Three elaborates the method used in the
study. Chapter Four presents the analysis of data collected from the field test in Vietnam.
Chapter Five discusses the conclusions, limitations, and recommendations of the study.
Chapter Two
A Review of Related Literature
Cooperative Learning
It is essentially the experience, the means, that fit human beings not to their external environment so much as to one another. Without the cooperation of its members society cannot survive, and the society of man has survived because the cooperativeness of its members made survival possible-it was not an advantugeous individual here and there who did so, but the group. In human societies the individuals who are most likely to survive are those who are best enabled to do so by their group.
Ashley Montagu, 1992
The great ideas of Ashley Montagu remind me of a Vietnamese saying: "Mot cay
lam chang nen non , ba cay chum lai thanh hon nui cao" (One single tree cannot be a
mountain but a high mountain can be conformed by three trees standing closely).
Societies are strong when people stand closely together, work in groups and help
one another in every aspect of our complex life. Where, when and how can this be
achieved? There is no doubt that cooperation and helping behavior must come from
schools where students represent the new buds sprouting on the trees of education in an
effective society.
Classroom learning through cooperative group work has its sources in
philosophical, ethical, and psychological writings of the past 90 years (Sharan and
Lazarowitz, 1980). First among the prominent forefathers of this educational orientation
is John Dewey (1959), as cited by Sharan (1980). His thoughts on democratic processes
inspired other writers who have made important contributions to the clarification and
development of the cooperative learning model, including Herbert Thelen (1963), John
Michaelis (1977). All of these educationalists share important ideas that comprise the
value base and intellectual underpinnings of cooperative learning.
In July 1975, the first International Conference on Cooperation in Education was
held in Tel Aviv, Israel. More than forty educators from Australia, Canada, England,
Israel, the Philippines, South Africa, and the United States gathered to discuss the theme
of cooperation, a gathering which resulted in the establishment of the International
Association for the Study of Cooperation in Education. Literature on cooperative
learning has also been prevalent since the mid-seventies, including the work of David and
Roger Johnson of the University of Minnesota (Johnson & Johnson 198 1, 1974), Slavin
(1983) of Johns Hopkins University, and Sharan (1980) of Israel. The researchers have
studied how cooperative learning task and reward structures affect learning outcomes
(Joyce and Weils, 1986). They state:
Important for us is the question of whether cooperation groups do in fact generate the energy that results in improved learning. The effect is largely affirmative- classrooms organized so that students work in pairs and large groups, tutor each other, and share rewards are characterized by greater mastery of material than the common individual-study. (p. 21 6)
It is mutual help and constructive interaction in the group that make cooperative
learning effective, as well as the fact that the group collaborates on a task that invites
cooperation (Webb, 1985). When carrying out a research in desegregated schools about
cooperative learning in the classroom, Shlomo Sharan (1990) and others fully agreed with
the observation by SIavin (1983) that:
Various elements of cooperative learning affect interracial relations primarily through the meditating variable of close interracial contact. (p. 86)
Johnson & Johnson carried out 122 studies from 1924 to 1989 to compare
cooperation, competition, and individualistic learning. Their data suggests:
1. Students achieve more in cooperative learning than in cornpet;'' I L I V ~ or
individualistic interaction and the results hold for several subject areas
and a range of age groups from elementary school age through adult
(Johnson, 1980).
2. Students are more positive about school, subject areas and teachers or
professors when they are structured to work cooperatively (Johnson &
Johnson, 1975).
3. Students are more positive about each other when they learn
cooperatively than when they learn alone, competitively or
individualistically; regardless of differences in ability, and ethnic
background, and whether they are handicapped or not (Johnson &
Johnson, 1975,1981).
4. Students are more interpersonally effective as a result of working
cooperatively than when they work alone, competitively or
individualistically. Students with cooperative experience are more
able to take h e perspective of others, are more positive about taking
part in controversy, have better-developed interaction skills, and have a
more positive expectation about working with others than students
from competitive or individualistic settings (Johnson & Johnson, 1975,
1978; Johnson, 1980).
How to teach cooperative learning
In order to work cooperatively, students need to be guided by their teachers or
professors to get collaborative skills. When working intensively with over twenty school
districts and several American colleges and universities on training staff in the strategies
of structuring cooperative interactions and teaching studeilts the skills needed to work
effectively with others tcommunication, leadership, tr::?t building, and conflict
resolution), Johnson and Johnson (1989) suggested an outline of the model of training as
follows:
A. Select a lesson. Teachers should start with one lesson and build slowly
as they and their students get accustomed to the "ncw" structure.
Cooperative learning groups have been shown to be especially
effective where problem solving, conceptual learning, or divergent
thinking are required.
B. Make the following decisions:
1. Select tne group size most appropriate for the lesson. The optimal
size of a cooperative group will vary according to resources needed
to complete the assignment (the larger the group, the more
resources avdab1e); the cooperative skills of the group members
(the less skillful the members, the smaller the group should be); the
amount of time available (the shorter the time, the smaller the
group should be); and the nature of the task.
2. Assign the students to groups. For variety of reasons,
heterogeneous groupings tend to be more powerful than extreme
hom*ogeneity. A lot of power for learning in a cooperative group
comes from the need for discussion, explanation, justification, and
shared resolution on the material being learned.
3. Arrange the classroom. Group members need to be close together
and facing each other, and the teacher as well as members of other
groups need to have clear access to all groups. Within the groups,
members need to be able to see the relevaui materials, converse
with each other easily, and exchange materials and ide;s.
4. Provide the appropriate materials. Providing one answer sheet to
be turned in by the group with every one's signature is one way to
emphasize the positive interdependence. Another technique is to
"jigsaw" the-materials so that each student has part of the
information needed and has a share of the responsibilities
associated with their piece of the assignment (i-e., reading to group,
researching and reporting back for discussion, etc.).
C. Explain the task and cooperative goal structure to students. A clear
and specific description of the task needs to be given coupled with an
explanation of the group goal. The group goal communicates that the
group memkrs are in this together and need to be as concerned with
other group members' understanding of the materials as they are with
their own. The reward system needs to be consistent with the
structure. f tltdents will understand the group goal more easily if they
are turning in a single paper that each group member is able to defend,
or can receive h a u s p ims on the basis of how well each group
member does, or will be able to skip the next quiz (or get extra recess)
on the basis of a group score. It is also important to establish criteria
for success as a class in order to make intergroup cooperation possible
and extend the cooperation across the class. It also necessary to
specify the basic behaviors you expect to see in the group so that
students have an "operational" definition of what cooperation is.
D- When the p u p s are working, the teacher needs to monitor how well
the goups are functioning; what skills are lacking, both related to the
subject matter, and to the interaction; set up a way for the group to
process how well they functioned and discuss how to do even better;
and intervene where problems are serious to help a group work out
their own problems. It is important to note that the cooperative group
does nOf take the glace of instruction, but instead translates it and
makes it tlseful. The teacher will still need to introduce new material
and students will need to research and study so that they have
something to share with their peers within the group.
During the process of carrying out the strategies listed above, teachers may wish
to suggest more effective procedures for working together and more effective behaviors
for students to engage in. Teachers may also wish to intervene and reinforce particularly
effective and skillful behaviors that they notice (Johnson & Johnson, 1987, 1990). The
following specifying desired behaviors are expected:
Having each member explain how to get the answer
Asking each member to relate what is being learned to previous
learning
Checking to make sure everyone in the group understands the material
and agrees with the answers
Encouraging everyone to participate
Listening accurately to what other group members are saying
Not changing your mind unless you are persuaded through a reasoned
argument (majority rule does not promote learning)
Criticizing ideas, not people
It is also recommended teachers not make the list of expected behaviors too long.
Emphasizing one or two behaviors over a few lessons is enough. Students need to know
what behavior is appropriate and desirable within a cooperative learning group, but they
should not be subjected to information overload.
When the groups start working, the teacher instructs students to cooperate and lets
them know they will not always be working in the same group. Much of the teacher's
time in cooperative learning situations should be spent observing group members in order
to see what problems they are having in completing the assignment and in working
collaboratively . Johnson and Johnson (1 99 1) suggest:
Whenever possible, teachers should use a formal observation sheet to count the number of times they observe appropriate behaviors being used by students. The more concrete the data are, the more useful they are to the teacher and to students. (P. 71)
But ii is unnecessary to count too many different behaviors at one time, especially
when the groups first start working together. At first teachers may want just to keep track
of who talks in each group to get a participation pattern for the groups. The current list of
students' behaviors includes contributing ideas, asking questions, expressing feelings,
active listening, expressing support and acceptance (toward ideas), expressing warmth
and liking (toward group members and group), encouraging all members to participate,
summarizing and checking for understanding, relieving tension by joking, and giving
direction to the group's work. These are all positive behaviors which should be praised
when they are appropriately present and discussed when they are missing.
According to Johnson & Johnson (1991) and others' experiences of cooperative
learning groups, student observers can be used to get even more extensive data on each
group's functioning. The observer is in the best position to learn about the skills needed
for working in a group. Whether student observers are used or not, sometimes a simple
checklist is helpful in addition to a systematic observation form. Johnson and Johnson
(1991) suggest some typical questions to ask on the checklist summarized as follows:
1. Do students understand the task?
2. Have students accepted the positive interdependence and the individual
accountability?
3. Are students working toward the criteria established for group work,
and are those criteria for success appropriate?
4. Are students practicing the specified behaviors?
Students must build mutual trust in order to work together. Trust building has
been considered as one of the most important skills in dealing with people at the
workplace. At school, this skill develops through cooperative learning in groups.
Johnson and Johnson (1991) argue:
To disclose one's reasoning and information, one must trust the other individuals involved in the situation to listen with respect. Trust is a central dynamic of promotive interaction. Trust tends to be developed and maintained in cooperative situations and it tends to be absent and destroyed in competitive and individualistic situations. (p. 2: 10)
Cooperative learning group method in teaching biology
20
In 1984, Lazarowitz,Braid, Hertz-Lazarowitz,and Jenkins carried out cooperative
learning group strategies in three schools of rural towns in California. The study involved
109 students from grade 10 to grade 12 taking a six-week biology course. The authors
came to the following conclusions:
1. Cooperative learning methods that use specific group rewards based on
group members' individual learning consistently increase achievement
more than control methods.
2. Cooperative learning methods that use task specialization may increase
student achievement more than control methods.
3. Group competition increase the instructional effectiveness of
cooperative learning in some cases.
4. Equal opportunity scoring procedures may have a positive effect on
student achievement.
Case Study
History, development and significant meanings
Case study methodology is most closely associated with the Harvard Business
School. This method of teaching has been used for more than fifty years and achieved so
much respect and success that it has been adopted for many other professional fields,
including law, medicine, counseling, nursing, political science, and social work
2 1
(Bickerton, 1991). Recently, teaching with cases has been supported by many educators,
Roland Christensen, a long time supporter and practitioner of case method teaching at
Harvard, points out numerous advantages of this approach in his new edition of
"Teaching and the Case Method" (Christensen, 1987):
1. The case method enables students to discover and develop their own
unique framework for approaching, understanding and dealing with
problems.
2. The case method supports a culture that places high value on review
and innovation. When faculty must prepare teaching cases, their
continuing contact with the world of practice provides a force for
change.
3. The case method of teaching is economically efficient. With carefully
crafted cases and trained instructors, it works well with large groups of
students.
4. The pedagogy suits the mission of training students not only to know
but to act.
5. Case study teaching is intellectually stimulating for the faculty.
6. It requires the faculty to explore not only what they teach but how.
Postman (1989) describes case teaching methodology as reporting an event, an
innovation or a project over a prolonged period of time by telling a tale or a story about
how it has involved. Narrative, description and explanation are highly valued and
utilized. Stakes ( 1985) agrees that case study methodology is becoming more widespread
in science teaching. Selma Wassermann (1994) predicted that , in the near future,
teaching with cases will be applied more frequently in schools not only for social studies
but also for science instruction.
Teaching with cases uses the instructional approach described as "Play-Debrief-
Replay" (Wassermann and Ivany, 1988). The whole process is often observed in
classrooms in combination with teaching for thinking, teaching for understanding, active
learning, cooperative learning and attitudes that encourage the empowerment of students.
Some teachers use the case method explicitly. They create tasks related to curriculum and
ask students to complete hands-on or "minds-on" investigative play, followed by
debriefing and then replay. Some teachers use the approach implicitly, moving from play
to debrief to replay in a clearly observable pattern but without using the labels
(Wassermann, 1992 b). According to Herreid (1994), the instructional approach should
have the labels because they present a specific scheme that is appropriate to different
subjects, different instructional levels and a wide range of participants.
The "play" stage requires that students, while working in groups for at least one
hour, participate actively in "mind play" with the study questions that direct each case.
Students are not pressured by questions that force them to arrive at an answer but they
gradually find out the "big ideas", which involve developing cases that allow for the
examination of certain significant ideas and issues, and productive answers by developing
a deep thinking about the case. Big ideas are extracted from the curriculum and form the
nucleus for a case (Wassermann, 1990).
In the "debrief' stage, students return to their whole class as usual and the teacher
uses skillful questioning and responding strategies to work with students' ideas and help
them reach for the deep meanings in the case and reason from the data. When the teacher
debriefs skillfully, students are interest and motivated to know more (Raths, Wassermann,
Jonas and Rothstein, 1986). This sets the scene for further study.
In the "replay" stage, students often review the supporting documents or the
background reading resources, as well as films and other materials the teacher considers
relevant to the continued study of the concepts being examined, to the build a broad
knowledge base.
The strategy of "play-debrief-replay" wants students to be responsible for their
learning. They acquire information not only from teachers' lectures but from creating and
gathering documentary resources and materials. When learning with cases, students
choose their own study methods and direct their own interactions. The strategy also
requires that the teacher creates the conditions in which all students' abilities can develop,
and flourish. While working with cases, Wassermann (1992) emphasizes this
instructional approach to t~each cases for social and science classes, she argues:
"Play-Debrief-Replay" is seen in operation in classroom where the strands of active learning, teaching for thinking, cooperative learning, and the empowerment of students combine to form the total learning experience. (p.797)
Recently, cases have had a strong appeal for students who are turned off by
traditional science courses oriented around a lecture format with a concentration on facts
and content rather than the development of higher-order thinking skills (Herreid, 1994).
Cases are most easily used in general education courses dealing with science and society
although cases alone cannot solve all the problems of education. Herreid states:
Although the case method can not cure all of the ills in the teaching of science, it is nevertheless ideal for the developxent of higher-order reasoning skills, which every science teacher claims they strive to instill in their students. (p. 228)
Case study in biology with cooperative learning group strategy
In a paper to the National Science Teachers' Association Conference, Reg Wild
and Steve Cardwell, of the University of British Columbia, propose the use of case
studies as an approach to teaching science. They argue that cases allow students to learn
from the past experience and build on what they bring to the classroom.
Case study and related strategies can be important focus for interpreting STS (Science, Technology and Society) Curriculum and support materials. Both sides of an issue are discussed with no answer given. Cooperative group work is often important part. (Cardwell and Wild, 1992, p. 16)
They suggest that the use of case studies is strongly supported by a constructivist
theory of learning.
In university level of biological science program, Hansen and Gottlieb of Modesto
Junior College (1990) write in support of the use of case method in teaching biology
courses as a means of implementing interdisciplinary education and developing critical
thinking skills in undergraduate biology majars. They express their dissatisfaction with
the traditional didactic method of lecture and regurgitation of facts. While they do not
want to discard the content, they do not believe that lectures are the best way to teach
biology. Instead, they recommend that:
Instructors provide a classroom environment in which students incorporate factual biological informaiion within a context raiher ihan a classroom in which they relate the discipline of biological science to their areas of the curriculum. The goal is that students become able to solve problems, that they engage in critical thinking, and that they apply these skills within the large framework of their educational and life experience. (Hansen & Gottlieb, 1991, p, 148)
Hansen implemented the case study method in her freshman biology class and
with major students. The result, again largely anecdotal because of the newness of the
process, indicated that the students felt the use of case study was successful.
According to the students, its importance was that the exercise connected
biological information, biotechnology, and everyday experience. Collaborating in group
work created a sense of camaraderie and community.
Case studies can be carried out not only by teachers with their narratives but also
by students. According to Zeakes and Fulwiler (1989), one of the best ways to actively
involve students in their education is to stimulate them through writing to learn. Samuel
J. Zeakes and Toby Fulwiler of Radford University, had a class in parasitology using a
writing-intensive approach with case study. They argue that writing would help lessen
the drudgery of rote memorization to which students are traditionally exposed and would
stimulate them to think.
Students of the class were assigned to read the chapter on trematodes from
Markell, Voge and John, 1986, as cited by Zeakes (1989). The chapter material was
presented and discussed in class using a lecture-discussion format in groups, Students
were exposed to the subject material for the case study via lecture, laboratory and reading
assignment. A five minute, in class writing exercise generated a complete caqe study.
The students were asked to originate a case study dealing with a parasite they had studied.
They were to present their written case study and then evaluated others' case studies (the
writer that received a highest mark from other students was a 20 year old Vietnamese-
American). Students seemed to enjoy doing the case studies on their own and the analysis
of their performance on an examination indicated that their understanding and retention of
the concepts were excellent. Based on the achievement Zeakes states:
Modifications of the case study approach could be adapted to almost any class, no matter what the size or discipline. For example, the case study approach would be valuable in classes in the health sciences such as nursing, medicine, dentistry, veterinary medicine, and medical technology. Adaptations of the case study format could be used in psychology courses, law courses, history courses, social courses, and science courses. The possible applications, with some creative modifications, are unlimited. (p. 34)
Since 1990, case studies have been used at the State University of New York at
Buffalo to teach a large number of biology courses in both laboratories and lecture.
Herreid (1994) draws several conclusions from these experiences: the case method
involves learning by doing, the development of analytical and decision-making skills, the
internalization of learning, learning how to grapple with messy real-life problems, the
development of skills in oral communication, and often team work.
In some cases, facts given by teachers also can be cases for students working
together with discussion and reasoning (Zeakes, 1989). A question like "Why is amylase
enzyme is necessary for digestive functions of mammalian animals?' could be used for
teaching with case stcdy (Yayer & Tweed, 1990).
Critics of the case study method
There is a bias toward collected literature of only positive results. The case study
method literature certainly suggested that the method had its critics. However, this
review has only been successful in finding one published criticism of the case study
method. This was not separately published but was a part of a work on a broader topic
(Drucker, 1954). Drucker argues that identifying opportunities is more important than
designing solutions to these positive and negative situations. The author also questions
whether it would be possible to prepare cases of sufficient quality so that, the problem
identifying would be developed. Drucker suggested that the student should first learn
analytical processing procedures in initial coverage at the comprehensive level. The
student should then learn to better supply these procedures with the case study method.
The students should not attempt to induce analytical processing procedures on their own.
Decisionmaking should therefore be based upon the specifically recommended analytical
procedures and not included procedures. This criticism, however, concerns only one
version of the case study method and not all versions.
Thus, regardless of its critics and praise, no matter whether case studies are written
by teachers, or students or given as facts, this approach can be applied in teaching science,
and particularly biology, combining with cooperative learning group methods. Joyce and
Weil(1986) advise that teachers develop a repertoire of models. They argue:
The teacher should view these models of teaching as ways of accomplishing a wide variety of purposes. Since no single teaching strategy can accomplish every purpose, the wise teacher will master a sufficient repertoire of strategies to deal with specific kind of learning problems he or she faces.. .The teacher's repertoire of models is paiticuliilly Lipitan; if he or she is rcsporisible for teaching many children in several curriculum areas. But even the subject-matter specialist, whose responsibilities may be confined to teaching a single discipline to fairly mature students, faces teaching tasks for which no single model can be completely adequate.(p. 20)
In order to develop a repertoire of teaching models, teachers must be flexible in
deciding which models are appropriate to various cultures, styles of learning, different
kinds of subject-matter, and adrninistrative/societal expectations of the school. On this
point, Joyce and Weil(1986) argue:
To develop a repertoire means to develop flexibility. Part of this flexibility is professional. Every teacher faces a wide range of problems, and if he or she has an equally wide range of teaching models from which to draw, he or she can generate more imaginative solutions to the problems. On the personal side, having a repertoire requires the ability to grow and expand one's potential, and the capacity to teach oneself more varied and interesting ways of coping with one's own need to develop. The environment for personal growth is greatly enhanced when people can define their present situations and see the alternatives. The growing, developing teacher can embrace more forms of experience, explore more aspects of his or her students and find more ways of helping them grow. (p. 21)
From these arguments it can be seen that any curriculum development work ought
to be accompanied by inquiry into teaching strategies appropriate for the purposes and
goals of the reform. In the case of the development of a basic science program for the
first- and second-year undergraduate programs in Vietnamese universities, the teaching
strategies proposed are applied with the intention of developing students' cognitive and
decision-making abilities in science as well as their social skills in working cooperatively
together.
Chapter Three
Research Methods
Description of the study
The ideas for this project emerged during my first three semesters at Simon Fraser
University. I am one of a cohort of Vietnamese students who came to Vancouver in 1993
to do a M.Sc in science education at Simon Fraser University. This was the first time 1
h2d gone abroad and I found the atmosphere at a Canadian university different from my
home university in Vietnam in many ways. I was not used to the informal atmosphere of
tutorial groups, or to professors who welcomed students' questions, or to students who
were willing to share their ideas with a great deal of self-confidence. In my first classes
in Canada, I was quite shocked. In Vietnamese universities students have to "sit
properly" without hats or caps, and are not allowed to eat, drink or chew gum in class.
When an instructor enters to the classroom students stand up automaticaliy to greet their
teacher and when the class finishes students again stand up to say goodbye to him or her
(teachers have been respected just second to the King). Everything is quite different in
Canada. Studen~s go to their classroom with a sandwich, a cup of coffee, or softdrink.
When they ask their professors questions, they do not need to stand up, and they can ask
questions at any time. Professors answer questions in a way that seems to encourage the
students to propose more questions; at my home university, students are sometimes too
shy tn ask questions to their insrJ!~ct_o-rs. Caoxiian students express freedan, self-
confidence and self-esteem in their classes. After immersing myself in Canadian social
life for a short time, I began to fix1 that our students at home suffer a lot from our
confucian culture. They lack social skills, which are neglected in our curriculum . And
we educators tack concern about students' developicg social skills before leaving school.
I remember when I was at home, I often used oral examinations to evaluate students in
my physiology courses. Although students could do the exams well they still lacked
confidence in speakklg. I asked myself the question: How could Vietnamese students
develop their social skills when taking science courses? .
In Canada I had to use computers to do assignments although I had never touched
a computer until a few weeks before coming to Canada. I learned to use computers and
gain other skills through the help of my coiieagues and professors, and I still feel indebted
to them. It reminded me that Vietnamese students lack a close relationship with their
peers in learning activities at school because of the "traditional" curriculum. f asked
myself whether we educators could do something to improve the situations. How could
we do it?
In my Canadian university classes, I was impressed that most professors had the
patience to listen, to appreciate their students' opinions in discussions. We students never
felt hun in school here- At home, my teacher often scolded me when I had a wrong
answer although I respcted him very much. I have asked myself why there was a
conflict in my feeling about what I have seen here and what I had experienced at home. I
asked myself : How could we build a good relationship between teachers and students
appropriate to our cuItures d cwtoms?
3 1
In my Canadian courses I have developed my self-confidence, trust-building and
reasoning skills gradually through the class learning activities, while at the same time
gaining a deeper understanding of the course content.
In contrast, Vietnamese students are indirectly set in an inactive mode of learning.
taking notes in class lectures, going home or to the librabry to memorize as much as
possible, and forgetting the course immediately after finishing their final examinations. It
is really hard for them to have a chance to get a deep understanding of science without
reading materials, discussions or opportunities to share their ideas with others. So my
fourth questions was : How can Vietnamese students get a deep understanding of
science? Could they learn from one another? Do they want to work together in a
competitive environment?
The preparation
Survey questionnaire
Based on the related literature on social context in Vietnam, especially in Dalat
University, I began my research with the three following expectations:
1. I believed that Vietnamese students accepted the curriculum as it is
taught now, and were willing to take an inactive role at school. I felt that they would only
be concerned about getting the credits required to be able to leave for work.
2. In a competitive environment, if students lose their scholarship they
have t~ pay high tulhoo fes , but if they win, they pay no tuition fees and get a modest
living allowance as well. Competition for scholarships is a big challenge for average and
low performance students. I felt that high performance students might not want to work
with others, especially with l ~ w e r performance students because they might see it as a
waste of time and energy. Lower performance students with inferiority complexes might
want to defend themselves and not bother their peers.
3. Vietnamese students do not have many opportunities to develop social
skills at school, In a time of rapid development, young people particularly need social
skills to communicate with others. However, I expected that students who took science
courses might consider skills like trust building, oral communication, self-confidence, and
self-esteem unnecessary for science-oriented work .
In order to check the expectations, I prepared a questionaire including ten
statements focused on the three main themes listed above (Appendix A). I planned to
apply the "student-centered" methods with whole-class discussions, case study and
cooperative learning in groups in hope of bringing about a change in my students.
Case study
I was looking for a case which would incorporate ideas from the first three
sections of my physiology course (blood , cardiorespiratory system, and gastrointestinal
system) in the physiology textbooks or science magazines. Finally I found a very
interesting case written by Nuland (1995). I translated the case into Vietnamese language
and wrote the publisher for permission to use it as a part of my lecture. The case entitled
"The beast in the belly" or "the Pig-Bel" (Appendix C), involvcd bacterial infectious
disease that causes the human body to collapse from unbalanced homeostasis, heart and
blood vessel failure, respiratory failure, intestinal gangrene, and mental disorders,
resulting in high mortality rate in affected countries like New Guinea, Cambodia, China.
According to Selma Wassermann (1994), we teachers do not have to write our
own cases. Wassermann states:
Not every teacher will want to consider writing his or her own cases. Teachers have other things to do with their time, and good teachers hardly find adequate time to do everything they want to do in the first place. There are lots of good cases already available for teachers to choose from. Why should teachers consider writing their own cases? (p. 39)
I chose the "Pig-Bel" because it combined the major topics which I wanted to cover in
the physiology course. This case could arouse students' curiosity to research other
fields such as microbiology, and biochemistry. Regarding criteria for choosing a case,
Wassermann ( 1994) suggests:
A single case will not, in the best of circ*mstances, deal with all the topics to be studied in the course. It doesn't need to. The case needs to touch on at least one topic, leaving the door open for further study through reading (texts, articles, stories), films, speakers, and other information -rich resources, as well as other cases. (p. 27)
The physiology course
I went back home to work at Dalat University on September 5, 1995 after two
years of study in Canada. At my university, I obtained permission to teach a part-time
class in physiology using cases. The course was based mainly on the "Textbook of
Human Physiology", by Guyton (1977), translated into Vietnamese by Gi Trong (19781,
and partly on the "Human Body in Health & Disease", by Wood (1983) and the
"Physiolo&"' by Beme and Levy (1988). I made 45 copies of each chapter, one for each
of the 42 students, one for one my colleagues, one for the Head of Department of
Education and the last for myself.
Application of the study
Background survey with consent form
The survey was carried out with 92 students from three different populations: 38
students from the second year part-time class, 28 students from the third year full-time
class, and 26 students from the fourth year full-time class. Preliminary to the main survey
I did a background survey to ascertain how the three populations differed. This included
a consent form in which students' willingness to participate in the research was clearly
indicated (Appendix E).
I was planning to do the survey with the second, the third, and the fourth year-
students because I wanted the survey to be completed by students who already
experienced biology courses and student life. Besides, I considered the survey result as
one of my significant data to confrrm the possibility of the generalization of my study to
both full-time and part-time classes.
Feedback from the pilot study
I piloted the survey with 6 students from each class and after making changes
b a d on their feedback, f finished the background survey with consent form on
September 22. It was e n c o m g that there were 100 % of students attending the three
classes were willing to participate in the survey and 8 % of them were willing to be
35
interviewed. (As is usual at Dalat University, about two-thirds of total students attended
class).
Doing the survey
The survey was camied out on September 26,27, and 28 respectively for the
fourth, the third, and the second year classes. I used Minitab statistical software to
organize the data. On the worksheets, there appeared to be very little difference in the
results from the three populations.
Here are the main themes which emerged:
The students wanted biology courses to be taught with STS (Science-
Technology- Society) information, with "student-centered" met hods through
class and group discussions.
The students liked to learn from their peers, to work together. They agreed
that the higher performance students should help the lower performance ones.
The students considered social slulls very important for their future
achievement in the workplace and they agreed that the biology curriculum
should have learning activities that help them develop these skills.
Encouraging by students' positive attitudes indicated in the survey, I started to
prepare for my teaching which would form the main part of my research.
Teaching with "student-centered" methods
The physiology course started on September 29. For the first lesson about 34
students attended the lecture. The class leader told me that day was special; usually only
29 to 32 students attended lectures. The regular lecturer Lam Ngoc Tuan was there to
watch me teach the course. I sketched out my plan to work with the three sections only;
lecturer Tuan would continue teaching the course afterwards. The plan was as follows:
I randomly assigned four heterogenous groups, regardless of experience, age,
and ability. I guided them to work cooperatively for the case study.
I would introduce the meanings of every section, its significant relationship
with other fields, books available in university library, and a schedule for the
course: three morning classes a week (Tuesday, Thursday, and Saturday) from
7:30 am to 10:45 am.
We had seven classes as scheduled:
September 29: Introducing the schedule, the history of physiology.
October 3 : Blood. Its functions and immunity mechanism.
October 5: Circulation. Heart and blood vessels.
October 7: Respiration. Lungs and gas exchange.
October 10: Ingestion. Functional mechanisms of digestive tracts and
digestive glands.
October 12: Case study discussion and course evaluation.
October 14: Self-evaluation and midterm examination.
e I would provide lecture handouts of each section for each student with
questions suggested.
I would give lectures by providing information on the general mechanism of
each physiological system and asking students to answer the questions or
discuss any problems related to the course.
I would supply the case study with questions and materials on October 7 for
the preparation of group discussion.
I would organize small group discussions about the case "Pig-Bel" for the
"play" stage and whole-class discussion for the"debriefy stage and the
"replay" stage (stages in the process of working with cases).
I would organize a midterm examination with ten questions. Two-thirds of the
mark would be based on the course content and the other third of the mark
would be based on the content of class and group discussions.
The first class took more than one hour to schedule the course work. Students
seemed to be excited and happy because they did not have to take lecture notes, nor did
they have to pay for photocopy costs as in other courses. After a short break I
commenced my new teaching strategy. I introduced the meanings of the history of
physiology as related to other sciences. Suddenly I asked one female student sitting near
to me.
"If you were a scientist of the sixteenth century, which systems of human body
would you like to study first? Why?"
After a little hesitation she answered, " If I were a scientist of that time I would
like to study the gastrointestinal system and nutrition because we need food to survive,
without food a person would soon die. We need to eat".
There was a big laugh because during the war food was a big concern for
everybody, and it still seems to be a keen concern in many remote areas around the
country. The class seemed to be excited, some students discussing something related to
my question. I asked the same question to a male student sitting in the middle of the
class.
"If I were a scientist of that time I would have chosen the circulation, heart and
blood vessels, because the heart is the most important organ of our body. If our heart
stops working or our blood vessels are broken, we certainly die."
" Can I put forward an idea? One male student in the left corner asked me to
allow him to speak.
"Of course. Please. " I encouraged him.
" I think if I were a researcher of the sixteenth century, I would have started with
the respiration system. I understand that every organ of our body is very important
especially the heart and blood vessels. We could not work well if we had no meals, but
we could stay alive for a month without food, with water intake. And it is very hard to
ask our hearts to stop working, and in a case where we bled gradually we could survive.
If we stop breathing for a few minutes we die immediately."
"I heard that a person would die immediately if she or he were hit right here,"
added another male student, pointing to the back of his neck. "We have a respiratory
control center here and we would die if this were severely injured.''
"What do you all thnk about this matter?" I asked.
There were no answers.
" Who agrees with the idea that we wouid have started to study respiratory system
first? Please raise your hand to show your approval." I proposed.
About 80% (27 students) of the class approved the statement. I asked students to
read the handout carefully about the history of this period. It was clear that in the
sixteenth century the scientist Michel Servet began his study with respiratory system and
William Harvey, before studying the circulatory system, also began his study with this
system first.
When we had a second break, I passed by a group of male and female students
standing by the front door in the hall, I heard one of the male students speaking:
"Oh my God! I got terrified when she called my name. I am sure we all won't
dare to attend this course the day after tomorrow. We will all stay at home!" They
laughed. They were not aware of my presence.
We continued our discussion and finished the class at 10:45. Three male students
approached me with smiles. One of them spoke first.
" Teacher, we really like this style of teaching and learning. Through discussion
we could learn many things not only the course knowledge itself but also ways to reason,
and think."
"Yeah. This is the first time I have experienced this method. I think we students
become more active and work independently with this process", the second student added.
"Yes. This approach makes us work harder but we understand better. We can
speak freely. I think with this method of teaching and learning we should take a multiple
choice examination". This student was the class leader and he wanted to consult with me
about an appropriate type of exam.
"Thank you for your recommendation'' I answered him. "I think in order to
develop your writing skills for this style of learning that besides reading and talking, we
should have a written exam. OK. We will think more about this matter. Thank you so
much for your participation and encouragement."
From the starting point that day I felt happy and easy in hope that the new
approach could be applied smoothly.
On October 3, I went to my class with a curious feeling, students might stay at
home as they "declared" in the hallway. On the contrary, I found the class more crowded
than the previous one. I told them about what I had been thinking and they burst into
cheerful laughter. We went on to discuss the blood system with the suggested questions
related to blood plasma and blood cells, their numbers, functions, genetic technology with
hemoglobin, immunity, blood donation and transfusion, and AIDS. Students seemed to
be getting used to discussion which entailed a great deal of participation.
On October $ 1 was planning to invite Tan, Lien (fellow CIDA-sponsored
scholars) and the Mead of Department of Education of Dalat University to attend my class
as camera operators and observers respectively. Unfortunately the students had a
biochemical exam in the afternoon so they stayed at home to prepare it without informing
to me ahead of time, only three female studsnts showed up. I was embarrased and sorry
for this accidental delay. We planned to have a double lecture for the whole day on
Saturday to compensate for the missing class that Thurday.
On October 7, the Head of Department of Education,Tan and Lien attended my
class as planned. We worked with chapter II: "Heart and Blood Vessels". The students
were not distracted by the camera or observers but they were a little inactive and quiet.
I asked two students about their general view of heart and blood vessels. Their answers
were uncertain. A male student confided the "trouble" to me with a sad voice:
" Please forgive us because we just finished an exam and half the class failed to
complete the questions. We felt sad and exhausted so we could not prepare for your
course properly. We are sorry about that".
I changed my strategy and reviewed the general structures and functions of heart
and blood vessels during class discussion. I also told them the story of the artificial earth
designed by American scientists. (By the year 2000 the scientists hope that they could be
able to create an artificial earth and free it into the universe without earth's gravity. The
artificial earth, could, in theory, help human beings live longer because we would not
have to move vertically but horizontally, free of gravity, and our hearts would not have to
work as hard as usual to pump blood). The students became active again and we spoke of
many things outside the questions but still related to the course. I got useful feedback
from the two observers which I tried to apply immediately, for example, giving students
enough time to think before answering the questions or waiting for students to speak
voluntarily instead of directing questions to individuals.
In the afternoon we worked with chapter III: "Lungs and Air Exchange". We
concentrated on the organization and mechanics of the respiratory system, pulmonary
circulation, gas exchange and gas transport, control of respiration, and especially the
environmental and developmental aspects of respiration. Although we tried to keep pace
with the schedule we felt comfortable with class discussions as usual.
On October 10, class discussion went smoothly with chapter 4: " The Digestive
System". We talked about the structures of gastrointzslinal system and gastrointestinal
motility, about gastrointestinal secretions, about digesiion and absorption, all in a
connection with health and diseases.
Students were asked to prepare the case study for the next class, They seemed to
be excited to work in groups to change the atmosphere of class discussion.
Teaching with case study: The ''Pig-Bel"
"Plav" stape
On October 12, we worked with the case "Pig-Bel" through group discussion as
the "play" stage of the case study. We had two rooms for four groups with 33 students
attending. Each group had a group leader and a secretary for group management, to write
down students' discussion and their attitudes respectively. The students had gotten used
to talking in the wholeclass discussion md they worked very weil in small groups for
more than one and a half hours with the 'big ideas" proposed as suggested questions
(Appendix D). We concentrated on the mechanisms of homeostasis, acid-base balance.
on body immunity with the functions of white blood cells. on blood glucose with blood
pressure and kidney function, and on structures and functions of gastrointestinal system.
At 9:00 am we took a break in order to move to the "debrief' stage.
"Debrief' stage
It took one hour for the "debrief stage". In the "debrief stage'' we worked in very
relaxed conditions; students were eatmg some sweets, cookies and even smoking
cigarettes (mostly male students). Each group had to present students' discussion resulks
and I was responsible for writing down their ideas to make the connection among the four
groups' work. Students did their job very well, and their individual accountability and
collaborative spirit showed very strongly.
We had a video camera and tape recorders but unfortunately that day we had no
electricity a ~ d my video battery would not last longer than an hour. My brother, who
was an "instant video operator", had to run to somewhere to recharge it. As a result. the
video tape recording was sometimes intempted, but the audio tape recorders worked vcry
well with all the groups.
"Redav" stape
After finishing the "debrief" stage we had about 20 minutes for the "replay" stage.
We talked more atbout the roie of trypsin, the ioxin of parasite roundworm Ascaris
lumbricoides, about interitis necroticans in Vietnam. Then I reconfirmed students'
discussion results by providing them the information of "the Pig Bel" which I coliected
from the "Microbiology'" by Prescott, Harley, and Klein (1990), the "Infectious Disease"
by Farrar, Wood, Innes, and Tubbs (19921, and the "Nutrition in Health and Disease" by
Anderson ( 1982), stating that "the Pig-Bel" was the enteritis necroticans, that it was
Clostridiurn perfringens and its fatal effect on human health as follows:
"Clostridium perfringens type A is a very common cause of food poisoning, and
Clostridium perfringens type C causes a much more serious necrotizing enteritis in
various parts of the world. C. pertiingens food poisoning is due to a heat-labile
enterotoxin released during germination of spores in the food or in the gastrointestinal
tract after ingestion. The clinical picture consists of diarrhea and abdominal scamps,
usually without fever or vomiting, Outbreaks usually follow ingestion of meats or
gravies. the classic vehic% is meat pie with a crust: the vegetative cells but not the spores
are killed during cooking; the crust maintains anaerobic conditions while the spores
germinate; and the bacteria release toxin as the pie cools. Necrotizing enteritis is almost
associated with invasion of the bowel wall by the Clostridium perfringens type C and
maybe due to the action of f)-toxin, which is a potent lecithin's that causes cell lysis.
Sporadic cases are seen around the world, in adults and especially in children. Epidemics
have been described in Northern Germany (in Dambrand) in the mid-1940s, and in the
Highlands of New Guinea during ritual orgiastic feasting on inadequately cooked pork
(fig-Bel), The illness begins suddenly with severe abdominal pain, vomiting, bloody
diarrhea, md shock. Pathological findings include patchy necrotizing lesions, which may
progress rapidly to segmental gangrene with gas in mucosa, mesentery, or regional lymph
wdes. Gas may be seen radiographically in the wall of small bowel. Treatment includes
supportive care with replacement of food and electrolytes losses and decompression of the
bowel. Penicillin G should be used intravenously in large doses and C. perfringens type
C antiserum containing p-antitoxin should be administered if available. Complications of
paralytis ileus, strangulation and perforation of the bowel may necessitate abdomen
exploration and resection of involved segments of the intestine."
The students seemed to be highly satisfied with their group work.
Course evaluation
At 10:30 am we moved to course evaluation work. I explained why we needed to
get feedback from the students to improve the teaching of the course. I emphasized that
there was no need to sign their name anywhere in the course evaluation sheet. It seemed
that they did not feel intimidated and were willing to write down their thinking about the
course work done over the couse more than two weeks. The content of the course
evaluation sheet was very similar to that of some North America Universities (Appendix
F). It included two parts: one was the good point and drawback of the course content, the
other was the good point and drawback of instructor's method of teaching. Finally
students chose the suggested statement evaluated the course and instructor based on 3
levels: bad, good, and very good.
Self-evaluation and midterm examination
On October 14, the midterm examination took place at the usual time, '736 am.
Before taking the exam, each student received a self-evaluation sheet to grade himself or
herself on the three sections of this physiology course. At first, they hesitated, perhaps
they afraid of giving themselves too high mark. I emphasized the advantage they would
get from a precise self-evaluation. The self-evaluation content consisted of two main
parts with six levels from 0 to 5 (0,1,2,3,4,5) considered as marks (Appendix G).
Depending on their self-evaluation, each student's total mark can be a maximum of 50 or
a minimum of 0.
It took 15 minutes to finish this work and we started the exam at 8:OO. It was a
150 minute written exam with 10 questions (Appendix H) in which two-thirds of the
questions referred to lectures and one-third to class and group discussions. The exam
would count for 40 % of the total course mark.
Data collection and analysis
The survey
Data analysis of the survey used as a combination of qualitative and quantitative
methods. Firestone (1987) agues:
When focused on the same issue, qualitative and quantitative methods of analyzing can triangulate, that is, use different methods to assess the robustness or stability of the findings. (p. 20)
In order to compare the result of the three populations (two full-time and one part-
time classes) descriptive statistics were employed with " One Way Analysis of Variance"
(ANOVA). ANOVA is often used to ascertain the differences among three or more
groups (Huck, Comrier, and Bounds, 1974).
The mugh data with a 3 scaled choice was coded as a number for positive, neutral
and negative choices. Each population would get ten averaged marks from the ten
statements. As a result, these three populations got their independently averaged marks
from the ten statements. The statistically significant differences of the averaged marits
among the three populations wouid be determined by ANQVA.
For example:
Statement 1 : Science courses should be taught with STS content.
Agree Disagree No opinion
3 marks for "agree"
2 marks for "disagree"
1 mark for "no opinion"
Responding to the above statement, population one (the third year full-time class) got 24
agrees, 3 disagrees and 1 no opinion. The population's averaged mark for this statement
was 2.821
Observation
Observations are a primary source of data in doing qualitative research.
"Observation is a research tool when it (1) serves a formulated research purpose, (2) is
planned deliberately, (3) is recorded systematically, and (4) is subjected to checks and
controls on validity and reliability" (Kidder, 1981, p. 264, as cited by Merriam, 1988).
There have been several reasons why investigators want to gather data through
observation. Merriam (1 988) argues:
As an outsider an observer will notice things that have become routine to the participants themselves, things which may lead to understanding the context.
The participant observer gets to see things firsthand and to use his or her own knowledge and expertise in interyreiing what is observed, rather i h ~ relying upon once-removed accounts from interviewers. ( p. 88)
Some parts of the checklist of elements likely to be present in my observations,
which are used by "several writers (Selltiz, Jahoda, Deutsch, and Cook, 1959; Goetz and
Lecompte, 1984; Patton, 1980; Taylor and Bogdan 1984, as cited by Merriarn), were used
to gather data as follows:
The setting: The physical environment of the class, the context, kinds of behaviour which
vary depending on circ*mstantial attributes; encouragement and discouragement,
examination stress, etc.
Activities and interactions: Students' interaction with the class and group discussions and
how they interrelated to the learning activitities.
Frequency and duration: Frequency and duration of student responses in discussions,
conflict and conflict management. The occasions that gave rise to the responses.
Subtle factors: Informal conversations among students themselves during the class break,
nonverbal communication such as the sense of a relaxed atmosphere, and gestures such as
nodding, smiling, laughing, yawning, etc.
Whole-class discussion
The whole-class discussion process of each section of the course included preparing for
the discussion, beginning it, encouraging participation, and bringing the discussions to a
dose as guided by Gastel(1991). According to Gastel, the thought of discussions in
science courses conjures up the inactive images of classroom, she argues:
By engagirig students in using material that they have encountered in lecture and independent study, discussions can aid them in retaining it and learning to apply it. Discussions are well suited to helping students
develop skill in reasoning, problem solving, and critical thinking, as well as in comuniczticn. They give students close contact with instructors who can serve as role models. In addition, they can give instructors useful feedback on what students are (and are not) learning and thus aid in improving teaching. (p. 61)
Whole-class discussion played a crucial part of my study, giving students chances
to participate in learning with the new approach prior to working with cases.
Transcriptions from class observations, with video support, looked for student
participation in whole class discussions. The descriptive analysis of the data is based on
three main themes identified as follows:
* Memorization-dominated discussion
Conflict and conflict management
* Male-dominated discussion
Case studv discussion
Baszd on the transcriptions of the "play", "debrief ', and "replay" stages, recorded
by the group secretaries assigned as group observers, the data is analysed with regard to
four main themes as follows:
Female-dominated discussion
Seeking information from other materials
Reasoning skill and deep understanding
Individual accountability
Self-evaluation and midterm examination result
Perhaps the most fundamental condition of creavity is that the source or locus of evaluative judgment is internal. The value of his product is, for the creative person, established not by the praise or criticism of others, but by himself. (Roger, 196 1, p. 354)
One of the more profound changes being supported for students in classrooms of
the 1990s is the shift of locus of control over student evaluation from being totally in the
teacher's domain, into that of the students (Wassermann, 1994). Self-evaluation is a tilt
in the direction of partnership, in which teacher evaluates students, and students evaluate
themselves, and the results are examined and compared in a collaborative effort at helping
the students to take the next step in their learning. Also, sometime teachers evaluate
themselves, and students evaluate teachers each other. The relationship between self-
evaluation and examination results reflects the students' skills of self-appraisal and self-
confidence and their achievement through these approaches to teaching and learning. The
data is analyzed descriptively for future application as well.
Course evaluation
Feedback from the course evaluation is considered as crucial data to evaluate the
success of the teaching experiment in this thesis work.
Interview
Interviews have commonly been used as a means of gathering qualitative data. In
order to elicit information from another person, a person-to-person encounter is the most
common form of interview used, and "group or panel formats can also be used to obtain
data" (Merriam, 1988, p. 7 1).
This interview was carried out mainly based on four kinds of questions that "can
be used to get different types of information from respondents" (Patton, 1980, as cited by
Merriarn, 1988) as follows:
Experience/ behavior questions, related to the students' past and present
experience with different approaches and their behaviour toward those
activities.
Opinion /value questions, concerned with the students' ideas about specific
matters concerning improvements to the course itself and teaching methods.
Feeling questions, aimed at understanding the emotional response of the
students to their experience and thoughts about the approaches.
Knowledge questions, explored what students consider to be factual
information regarding the research topic.
The transcription of the group interview was also analysed with regard to
several main themes as Bogdan and Biken, 1982, (as cited by Merriam, 1988, p. 77).
suggest.
The main themes that were coded include:
Students' impression of the approaches
Social skill focus
Deep understanding of the course
Strong competitive spirit I
Teacher-student rdationship
Suggestions for improvement in the content of physiology course.
Internal validity
The data collected in qualitative research is open to interpretation. The
aim is "not to find the 'correct' or 'true' interpretation of the fact, but rather to
eliminate erroneous conclusions so that one is left with the best posible, the most
compelling, interpretation" (Brornley, 1986, p. 38, as cited by Merriarn, p. 167).
The truth, in terms of reality itself, can never be grasped (Merriam, 1988). In a
sense for researcher "what seems to be true is more important than what is true"
(Walker, 1980, as cited by Merriam, p. 167)
Another difficulty associated with internal validity and qualitative
research is one of the basic assumptions operating within the research framework;
namely, that "reality is holistic, multi-dimensional and ever changing; it is not a
single, fixed, objective phenomenon waiting to be discovered, observed, and
measured" (Meniarn, 1988, p. 167). In real terms this means that qualitative data
gathered on one day may be different from data gathered from the same person on
another day given the contextual and circ*mstantial events surrounding the
collection of data. Data collected from class discussions, group discussions, and
especially group interviews was affected by the contextual and circ*mstantial
elements that surely influence its internal validity.
Fortunately, triangulation has been recommended as a strategy to promote
internal validity. Using triangulation, data from observations are accompanied by
course evaluations, self-evaluations, midterm examination, and interviews so that
data to be synthesized and analyzed to avoid excessive researcher's bias and other
problems as mentioned. The study, however, could not strengthen the internal
validity by using member checks and repeated observations due to time constraints.
Reliability
To what extent can the findings of the study be replicated? According to
Merriam (1988), reliability has been problematic because human behaviour is
never static. But " without reliability no scientific progress can be made toward the
accumulation of knowledge about relative stable causal laws" (Bednarz, 1985, as
cited by Merriam, p. 170). Fortunately, qualitative research is not based on the
isolation of laws of human behaviour. Merriam (1988) argues:
Rather, it seeks to describe and explain the world as those in the world interpret it. Since there are many interpretations of what is happening, there is no benchmark by which one can take repeated measures and establish reliability. (p. 17 1)
In fact, reliability and validity are closely connected in the conduct of
research:
" Since it is impossible to have internal validity without reliability, a
demonstration of internal validity amounts to a sixultaneous demontration of
reliability" (Guba and Lincoln, 198 1, as cited by Merriam, p. 17 1). Furthermore,
the reliability of a study can be assessed through various techniques of analysis and
triagulation (Merriam, 1988).
Strategies used in the study to promote reliability include the investigator's
position: a statement of the researcher's position vis-a-vis the whole class and the
group interview, and the description of social context of this study. Triangualtion
and an "audit trail" (Merriarn, 1988) showing how the data has been collected and
analyzed, have both been used to promote reliability.
External validity
Generally speaking, external validity has been concerned with the extent to
which the researchers for some time. In order to reach the requirements of external
validity, a thick description "so that anyone else interested in transferability has a
base of information appropriate to the judgment" (Lincoln and Guba, 1985, as cited
by Merriarn, 1988, p. 173), is employed throughout the data analysis process. The
data analyzed also emphasizes on some phenonmena that appeared in class and
group observations to provide comparisons available for users'; they "can make
comparison with their own situations" (Goetz and LeCompt, 1984, as cited by
Merriam, 1988, p. 177).
Chapter Four
Findings of the Study
Background survey
The survey dealt with three populations: one second year part-time class, one third
year full-time class, and one fourth year full-time class. The three populations differed in
age, knowledge, family location, educational background, and future ambitions:
The second year part-time class:
Total number: 42
Participation number: 38 (24 males and 14 females).
Average age: 33 years old
Social status: full-time workers.
Place of work : 78.95 % from outside Lam Dong province, 21.05% from within Lam
Dong province.
Ambition after graduation: 39.47 % returning to current jobs, 3 1.57 % upgrading
experience, 23.6 % doing research, 5.6 % taking graduate courses.
The third year full-time class:
Total number: 43
Participation number: 28 (13 males and 15 females)
Average age: 21 years old
Social status: full-time students, with 71.42 % from outside Lam Dong province, 28.57 %
from within Lam Dong province.
Ambition after graduation: 25% going to work, 35.71 % taking graduate courses,
35.71% doing research.
The fourth year full-time class:
Total number: 38
Participiition number: 26 (1 1 males 15 females).
Average age: 22.66 years old
Social status: full-time students with 61.54 % from outside Lam Dong province and
38.46% from within Lam Dong province.
Ambition after graduation: 57.69 96 going to work, 34.61 % doing research, 7. 69 %
taking graduate courses.
The total number of three populations participating in survey was 92 students.
Although they differed as listed above, their opinions toward school were fairly
consistent.
Survey
The survey included ten statements. The first two statements focused on the
content of biology courses which should be taught. Statement four, five, and six
concentrated on the teaching methods in biology courses. The last four statements related
to cooperative learning and social skill development.
Statement One: Regardless of the basic training program of Dalat University,
fhe contents of biology courses shouEtl nor be concrete and pure science.
' ABLE I . ACREElvEST PERCENTAGE OF STATEMENT ONE 1 CIaSs.
8
Agree (%) 1 Disagree (%) No opinion I%) i I i I
t year 7 1 -05 15.79 13.16 i I
I ; Third year 85. 71 10.71 i
Fburfh year 11.53 73.08
3.58
15.39
This was very diEerent from my first expectation. The students seemed to be
active and had a keen concern about what biology courses should be taught at school
(Table 1).
Statement Two: Biology courses' contents should consist of STS (Science-
Technology-Society) infomuition.
The data appeared that the more experienced and older the students were, the
greater were their concerns about the statement (Table 2).
TABLE 2. AGREEMENT PERCENTAGE OF STATEMENT TWO
Statement Three: Biology courses instructed with a combination of theory and
real-life applications by using student-centered methods stimulate students to develop
No opinion (9%)
0.00
3.57
2.85 d
I I
positive attitudes toward learning science.
Disagree (%)
0.00
Class # / Agree (8)
All of the second year part-time students who had work experiences and all of the
Second year
TABLE 3. AGREEMENT PERCENTAGE OF STATEMENT THREE
fourth year full-time students who were going to finish university courses soon
100.00
Third year 1
96.43 0.00
No opinion (%)
0.00
7.14
I Class # I Agree (%) Disagree (%)
0.00 Fourth year
t Second year
97.15
i 1
100.00 0.00
Fourth year
Third year
100.00
I 92.86 I 0.00
0.00 I 0.09
I
completely supported the idea that biology content should be instructed with a
combination of r h a - ~ y and reality. So did the third y e a fit!!-time students (Table 3).
This data indicates that the more experienced and older students tended to feel
more strongly in favour of the statement.
Statement Four: Class and group discussions of the course through case study
with STS content can help students develop deep understanding of science and social
skills.
TABLE 4. AGREEMENT PERCENTAGE OF STATEMENT FOUR
Class # Agree (%) Disagree (%) No opinion (%)
I Second year 100.00 0.00 0.00
Third year 82.14 0.00 17.86
F o u h year 92.30 0.00 7.70
It is easy to understand why the part-time students all agreed with the statement.
Almost all of them were used to Gixussims at their workplaces. The data again appeared
that the more experienced and older the students were, the greater were their concern
h u t this teaching approach (Table 4).
Statement Five: During giving lecture instructors shouldpropose questions
related to the backgroumi knowledge and encourage students to answer.
TABLE 5. AGREEMENT PERCENTAGE OF STATEMENT FIVE i,
Although the majority of supporting the statement was not as high as previously, it
clearly indicated that the students had positive view of this style of teaching (Table 5).
It seems that the evidence disproved my first expectation. The students' choices
indicated that they were hungry for information from STS content, that they wanted to be
taught with a combination of theory and reality, that they wanted to be active in their
study at school.
Learning from peers at school was appreciated Gut fewer students from three
populations supported cooperative learning activity (Table 6).
Statement Six: Regardless of their leveis of pe&-orrnnnce, students could learn
many things from their peers at school.
TABLE 6. AGREEMElNT PERCENTAGE OF STATEMENT SIX
Statement Seven: High pe@ormance students should concern and help the lower
pei$omance students in their study.
TABLE 7 . AGREEMENT PERCENTAGE OF STATEMENT SEVEN
I Class #
i Agree (%)
Second year 89.50
Third year 92.86
Fourth year 84.61
Disagree (%)
2.50
0.00
3.84
No opinion (5%)
8.00
7.14
1 1.55
There seemed to be a tendency toward self-defense in the three populations with
regard to this statement (Table 7). It is easy to understand why the majority of the part-
time students agreed with the concept because they did not have to compete with their
peers to get scholarships; all of them had to pay tuition equally. Among the full-time
students there remains a competitive spirit which still influences their perspective towards
cooperative learning, and maybe the last year students were concerned not to have
tutoring consume all their time.
In any case, the data showed that my second expectation was incorrect; there were
a majority of students at Dalat University wanting to work together cooperatively.
Statement Eight: Social skills such as oral communication, trust building, and
self-confidence need to be taught and practiced.
TABLE 8. AGREEMENT PERCENTAGE OF STATEMEN EIGHT 1 t 1 I i
Class #
Second year
Agree (%)
Third year i 75.00 I
Once again the second year part-time students supported this statement with the
92.10
I Fourth year I 84.6 1 I 0.00
highest majority among the three populations. Through their working experiences, the
Disagree (%)
3.57
15.39
students believed that social skills needed in dealing with people obviously needed to be
No opinion (%)
2.63
21.43
taught and practiced. The lowest majority was the third year full-time students who were
a little indifferent to these skills while the fourth year full-time had more concern about
them (Table 8). We could say, again, that the more experienced and older the students
5.27
were, the greater were their concern a b u t social skill development.
Statement Nine: School should have leurnirtg activities to get sttrdertts irwolved in
lea,mtng and practiced :he social skills.
TABLE 9. AGREEMENT PERCENTAGE OF STATEMENT NINE
Class #
Second year
Again, the older and more experienced students appeared to have stronger concern
Third year
Fourth year
about how university students could develop their social skills t k n the younger and less
Agree (%)
97.36
experienced ones (Table 9).
89.28
96.15
Statement Ten: me perfamance and success of students in the workplace after
Disagree (96)
I 0.00
graduating will depend very much not only on their qualifications but also on their social
skills.
No opinion (96)
2.64
0.00
0.00
TABLE 10. AGREEMENT PERCENTAGE OF STATEMENT TEN I I I I
10.72
3.85
I Second year I 86.85 1 2.63 10.52
Class # ( Agree (%) Disagree (%) I No opinion (%) I I
Third year f
Although the majority of supporting the statement was not as high as previously, it
I Fourth year
spealung, Vietnamese people want to work independently, rather than to speak. We have
60.7 1
84.61
14.29 25.00
3.84 1 1.55
a leading economic power because Japanese people know how to work cooperatively.
Johnson & Johnson ( i 984 j argue:
The industrial strategy of Japan is a good illustration of this principle. Japanese management has been quoted as stating that the superiority of Japanese industrial system is not based on the fact that their workers are more intelligent than are the workers of other countries, but that their workers are better able to work in harmony and cooperation with each other, a goal that U.S. companies have been working towards for years. (p. 17)
It seems good for the developing countries like Vietnam to follow the Japanese
model. It is especially important for young people learn how to study and to work
cooperatively.
Again the data evidence proved that my third expectation was not correct too.
Students of the three classes agreed that in order to develop social skills they need to be
trained and to practice through school learning activities. It was very interesting that the
part-time students with years of experience at workplaces approved very strongly of the
concept, while the third year full-time students gave weaker support to this matter. It may
be conluded that the more experienced and older the students were, the greater were their
concerns about social skill development.
In order to ascertain the significance of the data, statistics was employed with
one way analysis of variance (ANOVA) as mentioned in chapter III. Each population got
a different rr~ark for each statement. The survey had 10 statements so each population got
10 different marks (with a maximum of 3 and a minimum of 1). After computing I
arrived at the following quantitative data-
TABLE 11. ANOVA summary table for comparison of different averaged-marks of the
three populations
LEVEL N MEAN STDEV
Third year full-time 10 2.7353 0.1776
Four year full-time 10 2.7437 0.1890
Second year part-time 10 2.9470 0.32 13
ANALYSIS OF VARIANCE
SOURCE DF SS has F P
FACTOR 2 0.2874 0.1437 2.53 0.099
ERROR 27 1 S346 0.0568
TOTAL 29 1.8220
(df: degree of freedom, SS: sum of squares, MS: mean square)
With: df within groups is 27
df for between groups is 2
critical F found is 3.33 at level .05 and 5.28 at level .01
experiment F is 2.53 < 3.33 with p = 0.099 < 0.05
From the statistical analysis, it can be concluded that there are no significant
differences among the averaged-marks of the three populations (Table 1 1). This means
that all the students of the three populations had the same perspectives towards school;
biology course subject matter, cooperative learning, and social skill development.
Observations
The observation data was collected from two sources: whole-class discussion and
case study discussion as follows:
Whole-class discussion
As described in chapter DI, class discussion was a strategy that changed to adjust
the varying situations in the class. General speaking, in these first three sections of the
physiology course, the students appeared to participate eagerly in class discussion work,
but I would like analyze these following categories of activities in class discussions.
Memorization-dominated discussion:
When students had enough time to read textbooks and think about the proposed
questions ahead of time, they could relate the course background to their experiences, so
in class they were very active in discussing or proposing questions to the instructor
voluntarily. But the discussions were still weighted toward memorization. Here was the
observation supported by the camera when the students discussed the cardiovascular
system.
Q: "Tell me about the blood pressure in a normal body and in an injured case
where there has been bleeding?"
A: Doi: "First of all, I would like to talk about the cause of blood pressure
formation in our body. When heart contracts, I mean the ventricles, they push blood from
heart into arteries with very strong pressure: 90 mm Hg in right ventricle and 140 mm Hg
in left ventricle. The pressure inside the blood vessels varies with the condition of the
heart and the arteries as well as with other factors. In a normal condition the pressure
decreases as the blood flows from arteries into capillaries and finally into veins.
Ordinarily, measurements are made of arterial pressure only. You know we call it a
sphygmomanometer. I am sure that everyone here has experienced this equipment at
some time. In case of injury, bleeding causes low pressure, and since blood from veins
cannot not go back to the heart, heartbeats become weaker and slower resulting in death".
Vy: "Yeah, we have two kinds of blood pressure: the systolic pressure occurs
during heart muscles' contraction and averages around 120 millimeters of mercury. The
diastolic pressure occurs during relaxation of the heart muscle and averages around 80
millimeters of mercury."
A: "By the way you two mentioned the pressure being different in the two
ventricles." "Could you tell me the reason for the difference?'
All the students were silent.
I guessed they were thinking about the structure of the heart wall. I gave them a
metaphor: pressure made from a pump with a thick wall and pressure made from a
balloon. I really wanted them to think more about the function of the thick wall of the left
ventricle and the thinner one of right ventricle.
The class was still silent. My expectation was incorrect. I then mentioned the
evolution process of the heart from invertebrate to vertebrate animals with its structures
and functions. At the end of the class there was a male student who raised his hand ,
willing to speak.
Thuy: "I think the different pressures are caused by the structure of the heart."
"Could you tell me more about the different structure of the two ventricles?'I
asked him.
The student seemed nervous about this question. His eyes were fixed on the
hadout, trying to find the right answer there.
Fortunately there was another d e student wanting to share his ideas,
Dung: "I think the different pressure made in the two ventricles is a evolutionary
process. (He repeated what f had said) The thicker the heart wall is, the higher the
pressure the heart causes. h order to pump blood from heart to lungs, the heart doesn't
have to work very hard because the distance from heart to lung is very short so the wall of
the right ventricle is thinner than that of the left one. (The student knew how to reason,
good). By contrast, in order to pump blood from the heart to the rest of the body with
exception of the lungs, the left ventricle needs a strong and thick wall to form a high
pressure. This process can explain why left ventricle could have 140 rnrn Hg of pressure
when contracting."
The class appeared to agreed with him. When a decision-making process was
required, 100 % of the students raised their hands to support the answer. Obviously it
took a long time for the students to figllre out the problem through an available metaphor,
and then to use reason. They often accept the concepts inactively.
The second scene of memorization-dominated discussion was as follows.
It was a Saturday afternoon. We were working in a relaxed but serious
atmosphere.
Q: "Could you please tell us the cause of the difference in the air components in
inhaling, resting in lungs and exhaling ?"
Nguyen: "Hm ... I did not think carefully about this so I could not say. I'm sorry."
Hai: "I don't know actually. From the diagram I can tell the difference but I
haven't figured out the cause of it."
Thinh: "Yeah. I think there is a special reason for the difference but I don't know
what it is either."
Usually the students just accept a concept, and memorize it automatically. They
can answer "how" and "when" questions but they can hardly answer "why" ones. In
d e r to improve this situatioii I fbi& tfre physiology course needs to go deeper into the
mechmkm of tfk- physiohgicd pwesses wit!! dizgrzms md metaphors illustrated.
Conflict and conflict manapement
Sometimes in class discussions, students wanted to protect their opinions when
speaking, and had serious arguments whenever they had conflicts with their peers' ideas.
Here is an example from class observations.
The average life span of red blood cells (erythrocytes) in the circulation is 120
days. From 10 % to 20 % of senescent red cells break up within the blood stream, where
the liberated hemoglobin is bound to a specific carrier protein, haptoglobin. Some plasma
hemoglobin is cleaved intravascularly into globin and heme. The latter binds to mother
carrier protein, hemopexin. Both complexes and the great bulk of senescent red cells are
cleared from the circulation by the liver and spleen; the liver for catabolization and the
spleen for macrophages.
We mentioned jaundice (yellow skin) of newborn infants.
Q: "Why do jaundice symptoms appear in new born infants?"
Vy: "Jaundice caused by an excess amount of bile in blood. I think when a baby
starts to take milk, the infant's liver has to produce a lot of bile because milk has fat, so
the abundant bile would be in blood stream and this would cause jaundice."
Chanh: "I don't think so. Infant jaundice is caused by the decrease in the number
of erythrocytes. During the time the fetus is nurtured in his or her mother's body the baby
doesn't have its own respiratory system connected directly to outside, so he or she needs a
very high number of red blood cells; 7 millions/ mm3 of red blood cells to get enough
oxygen from the mother's blood . When the baby is delivered it breathes with its own
lungs so the number of red cells becomes excessive. The tiny body doesn't need so many
tiny body cannot use up the bile so biliverdin moves freely in the blood stream and makes
jamdie appear."
Vy: "I don't think so. We should relate the case to acute hepatitis B. The
jaundice caused in hepatitis B is different from infant jaundice."
Chanh: "Yeah. Jaundice in acute hepatitis B is another thing. In newborn infants
I am sure that it is caused by the sudden decrease of a large number of red cells."
Chieu: "In my opinion, I believe that Vy's idea is right, jaundice caused by
excessive bile in blood stream. Vy was right on that point. Jaundice can be caused by
many reasons: blockage at the bile gall duct by parasites, for example. I also agree with
Chanh about infant jaundice. Chanh' s idea was completely correct."
The atmosphere of discussion sometimes became intense because ideas conflicted;
the students had a propensity to protect their opinions and try to prevent themselves from
being hurt. Fortunately the students were very friendly to their peers and gradually they
recognized their wrong ideas and were willing to accept others' right ones. The situation
usually became reconcilable though conflict management by third parties who knew how
to appreciate others' opinions.
MIstle-dominated discussion:
In class discussions I found that the voluntary speaking was weighted to male
students. In chapter I, blood system, among 14 students of voluntary ideas expression
there were 1 1 males and 3 females. In chapter III, respiratory system, there were 12 male
students spoke voluntarily while only 4 female students did. Here is the table of the
difference between male and female speaking voluntarily.
TABLE 12. MALE-DOMINATED 1
Chapter #
Blood svstem
Cardiovascular
Respiratory system
Digestive system
[SCUSSION
Male volunteers
(Number of speaking
studentsrnumber of attending
students)
Female volunteers
(Number of speaking
studentslNumber of attending
students)
3/15
Although the numbers are too few to warrant the use of statistics the ratio of male
and female volunteers listed above begin to suggest a phenomenon of male-dominated
discussion (Table 12).
Case study discussion
Female-dominated discussion
In group discussions in the "pltiy" stage, in contrast with the class discussions,
female students eagerly spoke to their peers. Female students that started the discussion
in all four groups (Appendix D). The following table shows the different frequency of
speaking between male and female students.
TABLE ! 3. FEMALE-DOMINATE DISCUSSION I I I
Group # Male volunteers
1 (Frequemy of I
I Female volunteers
(Frequency of
students) / students) I 1 speaking/Number of attending speaking1Number of attending
One
1 Four I 514 8/4
Two
Each student expressed her or his ideas at least once. There was a female student
916
in group I who spoke five times. Although there are not enough cases (one case only) to
143
1 314
use statistical analysis, the ratio of female and male students expressing their ideas give a
514
picture of female-dominated discussion in all groups except group two (Table 13).
Ironically, in the "debrief' stage all the presenters for group work were male students,
female students played a secondary role only, adding supplementary ideas to the case
study activity. It could be interpreted that maybe the female students felt comfortable
speaking in small groups, especially in a time limited discussion. It appeared that group
discussion could be a good way to motivate female students to speak more frequently as
compared with class discussion.
Seeking more information from other materials:
When preparing the course at home the students certainly sought more
information related to the course and especially to the case study, the "Pig-Bel", from
other materials rather just than the handouts. The students knew the detailed information
of this bacteria; an obligate anaerobic endospore-forming, gram-positive rod, strong gas-
producing. The students can identify the bacteria's name and its pathological cause; it is
very commonly found in soil, aquatic sediments and intestine system. Because of its
spores, contaminated food that has not been heated sufficiently still contains C.
perfringens. In a favourable environment, especially in rewarmed meat dishes if large
amount is ingested, the endospores can germinate, and an enterotoxin produced during
spomlation in the gut causes hypersecretion. Severe diarrhea comes from this symptom.
Clostridium perfringens produces a neurotoxin so it causes disorders of the nervous
system. The patient's very large abdomen is caused by its gas producing tendency.
Here are some short excerpts from my students' discussions (Appendix D) which
indicate that all the four groups' members contributed to their group work by seeking
more information about the case from other materials, identifying the name of
Clostridium and the infectious disease in Vietnam.
Hue (group I): "I think the "Pig-Bel" disease is caused by Clostridium
perfringens.. . . 9'
Anh (group II): "I'm wondering whether enteritis necroticans in our country
could be the "Pig-Be" or not. Symptoms of the two diseases are very similar t r ~ each
other. In my own opinions, the "Pig-Bel" is enteritis necroticans."
Thanh (group mj: " Listen to me, people. I just found something here. We can
come to a conclusion about whether the "Pig Bel" is enteritis necroticans. They say (she
reads the book aloud) about "Gas producing enteritis necroticans" in Vietnam as follows:
Caused by Clostridium ..."
Le (group N): "...I think this patient had diabetes so the symptoms were a little
different from our enteritis necroticans. This "Pig-Bel" might be enteritis necroticans ...."
When seeking more information from other materials the students related the
physiology background to their own experiences from work to provide very interesting
p u p discussions. Here an anecdote of their experiences' sharing with group peers:
Trung (group I): 'The case study did not say that this disease happened in our
country but according to my experience through many years working at QN hospital, we
have had many similar cases, if not say exactly same cases. We call it enteritis
necroticans. The clostridial toxin causes the lack of oxygen in certain areas of intestine.
Amputating the infectious parts of intestine through emergency operation is the only one
method that we have to treat enteritis necroticans for a severe infection of the bacteria ..."
Chung {group Hj: "...Through more than 8 years working at LD hospital as a
clinical technician, I think that the "Pig-Bel" disease is widespread in Vietnam. We often
confront with the same symptoms of the disease although patients' bodies are not usually
bloated and swollen as was Grace's."
Ngoc (group IV): "..,The clinical symptoms are very similar to enteritis
necroticans which is widespread in Vietnam; bloated abdomen, vomiting, bloody stool
including black feces, respiratory failure, low blood pressure. I am wondering whether it
is the "Pig-Bel" or not."
From the transcripts of the discussions of the four groups working independently,
f found that every member of the group sought more information from other materials as
well. Here are the summary of their "findings":
The case Tig-Bel" did not give any detailed information about the
Clostridiurn's toxin release and the affects of the toxin on human body.
Through other materials students could understand the mechanism of toxin
effected to the nervous system.
The case has no information about the species of Clostridium. Through other
materials and their own experiences the students could identify this bacteria
was C los~d ium perfringens .
* Tfie case did not mention the "Pig-Bel" in Vietnam. Based on their knowledge
ad experkmxe, &z s?&ents cmfd 5gwe ozt t h t t91 disease is the eomiion
enteritis necmricans in Vietnam
reason in^ skills and d e e ~ understanding
As described above. in whole-ciass discussions, the srudents reveaied heir
memorization ability more strongly than their reasoning skill. Through contact with the
case in group discussions, the students became more active and independent on their
knowledge, experience, and especially reasoning skill. By so doing the students were
able to gain a deeper understanding of the course and other fields related to the course.
They could identify the reasons for the patient's symptoms by going from one step to
another to ascertain the mechanism of the bacteria infection. From their physiology
background students knew that usually there are about 6000 - 8000 / mmbhite cells in
blood stream but in this case, the white cells increased to 28.500/ mm3. This means that
there were invasive microbes causing inflammation in the patient's body. Clostridial
enterotoxin is a neurotoxin that is absorbed from the gut and blocks acetylcholine release
at neuromuscular junctions by binding to the synapses of motor neurons and preventing
the release of the neurotransmitter acetylcholine. As a consequence, muscles do not
contract in response to motor neuron activity, and flaccid paralysis results. The activity of
enterotoxin could explain why Grace, the patient could not walk and feel her hands and
legs within 48 hours of eating the contaminated food. Besides, the bacteria's enterotoxin
produces a large quantity of gas (mainly CO,) which blocks blood circulation in intestine
because C 0 2 enlarges the vein system. With absorbing functions through the intestinal
wall blocked. fluid went out to her abdomen cavity by inactive diffusion. Gangrene set
in. Enterotoxin also caused skin capillaries to disfunction; blood vessels can not contract,
then the patient's skin became blotched.
Here are some excerpts from the transcrigts of the group discussions
(Appendix D).
Cuc (group I): (Her voice sounds a little weakj "I am thinking that the patient's
skin symptom was probably caused by skin gangrene. The bacteria's toxin was
responsible for this. And I also believe that the toxin blocked intestine peristalsis and
rhythmic contractions that normally push along the intestine's contents. Water in the
intestine couldn't 'be absorbed into the blood and it came out of the intestinai wall to her
abdomenal cavity. Why was the patient's abdomen so large? I think this symptom can be
attributed to gas producing. Not only her abdomen but her whole body was bloated,
right? The blockage of body liquid with absorption failure, and kidney failure resulted in
the whole symptoms."
Chieu (group Ifj: "...An excess of ure, and potassium in her body resulted in a
disordered acid-base balance, and whenever potassium becomes abundant in our body, the
transmission of nerve impulses through nerve cells would be blocked. That evidence
could also explain why the patient became paralyzed."
T. Huong (group III): "Yeah. Diabetes makes our body become weak to resist
harmful bacteria. That's why the number of white blood cells increased very rapidly: 28
thousands/mm3 in this case. Clostridial toxin binds to the synapses of motor neurons and
prevents the release of the neurotransmitter acetylcholin ..."
Phong (group 311): "Because of enteritis necroticans, water and food could not go
through the dead intestine. The blockage caused nausea, and vomit and the liquid went
naturally from intestine to abdomenal cavity based on the mechanism of diffusion. The
patient's girth became larger not only because of gas in her intestine but also because of
the liquid in her abdomenal cavity ..."
Ngoc (group IV): "Yes. Because children have weak immunity to attack the
invasion of the bacteria. Besides, our children's guts in general are the habitat of
parasites. The roundworm Ascaris lumbricoides ieleases a special chemical that can be a
trvpsin inhibitor. Trypsin is an enzyme that could destroy clostridial toxins. And one
more thing that is important is sweet potatoes in our country are still a main source of
starch for meals in many countryside families which are too poor to bay rice. So that's
why our children often get this disease more than adults."
Although the students were concerned about the general facts they collected, they
could understand tne mechanism of diffusion and know how reason to figure out the
cause of the patient's bloated body. By reasoning the students could prove that the
disorder of acid-base balance (one factor of homeostasis) caused the transmission of nerve
impulse to be blocked and paralysis to finally result.
The case study did not discuss the reason for the patient's intestine being
paralyzed. Understanding the functions of the bacteria's toxin, the students found the
reason for the paralysis by ascertaining the mechanism of the synapse-toxin binding.
Again they could get at the cause of vomiting and the bloated abdomen by getting deep
understanding about the functions of diffusion and absorption.
By reasoning, the students knew vihy children would be more likely to get the Pig
Be1 than adults. When sharing their ideas with other peers, the students could provide the
whole class a chance to get a deeper understanding of the functions of trypsin not only for
digestion but also for body resistance to foreign materials. The functions sometimes
blocked because of a close relationship with other factors such as roundworm Ascaris L.
and a "papain-like substance" as one student proposed.
In discussion the students had a tendency to emphasize the mechanism of human
body functions. Here are some short statements that illustrate this tendewy in group
work (Appendix D).
D. Huong (group HI): "'Clostridial toxin causes gangrene. Mechanism of
gangrene is a lack of oxygen, nutrients, minerals and water which come from the blood
for tissues' consumption. Once gangrene appears, bleeding will be a consequence ..."
Le (group N): "The mechanism was clostridia germinated rapidly with their
toxin released blocking the neurotransmitter acetylcholin so her intestine became inactive.
Fluid went through from the intestinal wall to abdomenal cavity and it made her abdomen
swollen.. ."
Class discussions mainly concentrated on the course topics and partly on society
and technology aspects (health and disease). The Pig Be1 mentioned some topics from the
course such as the role of white blood cells, blood glucose, blood pressure, homeostasis,
and functions of intestinal system. The case opened many directions for students to figure
out the mechanics of every symptom by applying their knowledge of physiology.
Through discussions, students could share their ideas and get a deeper understanding of
the course.
Coo~erative moup work and individual accountabilitv
3n the "debrief' stage, the spirit of cooperative group work and accountability was
evident. The students had a great sense of their groups' work and their individual
responsibility when representing their ideas in this stage, and this was especially true of
the female students.
We started the "debrief" stage with the first group. The students decided who
would act as a representative for the whole group. There was one male student with clear
and strong voice who reported on his group's discussion. He related the patient's
symptoms to the disorders of homeostasis mechanisms usually caused by the patient's
chronic diabetes. Her immune system was too weak to resist the attack of foreign
invaders 24 hours after eating a small amount of pork. She just ate very little pork, she
became ifl. The students were sure that only Clostridium perfringens can cause this
disease.
A female student from this group immediately assisted her group peer with some
more ideas that he had not completed. She talked more about the patient's circulation that
became disordered after intestinal gmgreoe and kidney failure took place. She thought
the patient's abdomen was bfoatd because body fluid wzs b!xked.
It was very interesting that the accountability of the group member turned out very
obviously when a male -dent of group I talking about papain. The following excerpt of
the "debrief" transcript could prove the meaningful spirit as mentioned.
Dai: "I would like to add this ideas. The case study does not tell the name of the
substance in sweet potatoes which destroys trypsin. We discussed it and we do not know
its name but we can guess it by relating to biochemistry knowledge. Almost every kind
of ;uit or starch-produced source which contains a milk-like liquid, such as pnpayu or
sweet potatoes, has lots of papain, a natural enzyme which can destroy protein. So
whenever we take sweet potatoes alone, for example during the war when we had to eat
sweet potatoes all the time, we felt an unpleasant heartburn. Sweet potatoes have papain
which destroys trypsin, I think."
The group was successful in dividing the presentation task, the male student
presented the group work and did very well in giving the class a clear picture about the
affects of the bacteria and its toxin to the patient's body through physiology knowledge.
Three students wanted to complement his ideas to improve their group's work. In group
discussion, they did not mention the chemical mechanism in sweet potatoes which
prohibits the function of trypsin, but in the "debrief' stage the male student of the group
talked about this chemical substance. He believed that any kind of fruits or vegetables
w%ch contain a milky liquid have papain, a natural enzyme which occurs in papaya. This
enzyme can hydrolyze protein, so he felt that sweet potatoes have papain which can
prohibit trypsin function. His deductive reasoning, although it needs to be considered
more, could be seen in the spirit of cooperative working and individual accountability.
There was no conflict among these groups in the "debrief' stage. Group 11 stated
that they had the same discussion and they also had some more special ideas related to
this disease in Vietnam. They were sure that the "Pig-Bel" was the enteritis necroticans
disease to which has been atti-ibritd deaths of Vietnamese children living in New
Eko~omir, Areas (YEA) or remote places. Those fmilies live In Oifficdt situations so
their children are malnourished, and their weakened bodies are susceptible to attack by
parasites and Clostridium perfringens, When tested, the number of parasites is always
paralleled by the number of Clostridium perfringens. The students figured out that
78
roundworm Ascaris Lumbricoides secretes a substance inhibiting trypsin's functions so
the roundworm can take away the nutrition from food intake. Trypsin becomes inactive
so the enzyme can not destroy clostridial toxin, which results in the "Pig-Bel".
The spirit of cooperative group work and individual accountability in this group
was also very high. There was a male student wanting to clarify the mechanism of the
patient's paralysis symptoms. He emphasized: "Clostridium perfringens produces
neurotoxin, and this toxin is a kind of enterotoxin, a kind of protein. The neurotoxin
blocks acetylcholin release at neuromuscular junctions by binding to the synapses of
motorneurons and preventing the release of neurotransmitter acetylcholin. As a
consequence, muscles could not contract in response to motor neuron activity, and a
flaccid paralyze appeared". Another female student then continued his demonstration;
she mentioned the mechanism of diarrhea. The enterotoxin made the gut hypersecretion
resulted in a onset profuse diarrhea; lots of clostridia are usually found in cultures of feces
of patients. She also talked about the mechanism of vomiting which happens when the
pressure between esophagus-stomach and the intestine are different. When gas release
caused the obstructed intestine to contract, the pressure in gut became considerably higher
than that in stomach so the patient had to vomit to balance the pressure in the
gastrointestinal system. Physiologically speaking, the student understood that vomiting is
a reaction to protect the body from foreign invaders or toxic materials taken in from food.
Similar to other groups, the assigned student presented his group's work very
articulately and other members added more ideas to convince the class about their
understandings. In group discussion the students did not mention the mechanisms of
diarrhea arrd vomiting, but in ihe "debrief" stage one group member wanted to clarify the
patient's s y ~ ~ p t s m bj gokg deeper into the msh;inisns of diarrhea vomiting which
protect the human body from toxic invaders.
While sharing the ideas of the other two groups, group stdl had their own
concern about the case study as follows: The patient's body was bloated, her original
weight was 125 pounds and before operation took place, it had gone up to 185 pounds: 60
pounds, almost 30 kilos difference. Due to the kidney failure, and intestinal gangrene,
body fluid absorption was blocked and it moved to her abdomenal cavity. The mechanism
of fluid movement here is inactive: fluid diffused automatically from the higher
concentration to the lower concentration. Her intestine was blown up with gas but gas has
very little weight so her sudden weight could be attributed to water intake blocked both
orally and intravenously. The enterotoxin released caused intestinal wall hypersecretion
and chlorides ions while inhibiting absorption of sodium ions.
The spirit of cooperative group work was also high with this group. When sharing
the same understanding, the students wanted to give more demonstrations for fluid
blockage and diffusion, and to clarify aspects of the diarrhea mechanism.
It seemed more difficult for the last group to present their ideas because of the
excellent contributions of the other three groups but the group was ready to debrief. One
=embers of the group talked about the relationship of the "Pig-Bel" to tetanus and gas
gangrene. Another mentioned that the patient's skin blotches were caused by blood
circulation disorder and enterotoxin causing subcutaneous hemorrhaging. Even though it
was the last group to present its work, the group members were active in discussion and
had a keen concern about the differences between gas gangrene and tetanus, which were
not mentioned during group discussion. They also raised the new subject of subcutaneous
hemorrhaging.
In short, whenever a group member presented the group's work, other members
added their ideas to complement their peers' presentation. During group discussion, I
could sometimes see conflict and confiict management. But in &e "debrief' stage there
was iio conflict: w?&iin &ese p i i p s dl st;tiCeiits appeared to have a cmpers:!-;e spirit,
and individual accountability beyond my expectations.
Interview
Interview data is analyzed based on several main themes. This rriangulation
method of data analysis will strengthen the validity of the thesis.
Students' impression of the approaches
As mentioned in chapter HI, some students had experienced the "student-centered"
method at their workplace and they were interested in the methods of instruction. But for
most of the students, this was their first chance to get involved in class and group work
discussions. When the students were used to learning with the new models, they really
appreciated and liked the approaches. Here is the excerpt from the transcript of the
interview.
Do;: "For me, I actually got used to learning with these methods of teaching at
my institute. I have worked at the Vaccine Institute in Nha Trang for seven years as a
technician of the B.C.G Producing Department. Recently our Institute has had many
training programs provided by UNESCO arid many professionals have come to our
Institute for short-term training programs. They speak English, of course. They teach
courses by using an overhead projector, and handouts are available. When we go to class
we just discuss what is suggested in the handouts. After finishing a section, we have to
take an examination. They want to make sure that we understand the previous section
before taking a new one. In general, I really like and appreciate these methods very
much."
Vy: This is the first time for me to learn with these methods of teaching and
learning. I feel 1 like getting involved in discussions even though sometimes the
8timphez was i d l y szzhiis with conflicting ideas, or when we could not f i d a right
answer."
Ky: "...I think the methods help students to work harder and better. I could
uode~tand md remember the couise content ~ g h t away in class. I didn't have to spend
my time so much to memorize it at home."
Le: "... This is the first time 1 took science course with these new methods.
Usually I am very quiet so 1 often got terrified if I had to answer questions. When 1 go?
familiar with the methods of learning, I found it interesting."
Huong: "I have the same feelings as Le does. I feel it is helpful to learn science
like this."
Reflecting the data from the survey (Question #4), the students agreed that the
teaching approaches made students work harder but better. Class and group discussions
helped them to develop a deeper understanding of science.
Social skill focus
Before 1985 Vietnam had a movement of group work at schools in which high
performance students had to be responsible for low performance students' learning
improvement. Each group had at least one member of Communist Youth Party (Doan
vien Dean Thanh Nien Cong San).
In order to get an understanding of the student's perspectives towards the new
approaches they had just experienced, 1 asked them to reveal their ideas by making a
comparison between two learning activities. The following excerpt from the interview
transcript gives their opinions on this matter.
Vy: "I think, we were at high schools before 1985. At that time, I remember we
had a kind of group work. It was a "national movement" which required students to work
togetkr. High achieving students had to help low achieving students to improve in their
learning. At least one of the group members had to be a Communist Youth partner so we
felt it was something mandatory and political." (laughing).
Thinh: "Yes. In 1980 when I was in secondary school, we had a group learning
movtmerri. High p z f o m c e sitidsfiis had io help lower performance students. i used to
be good at math and I had to take care of two peers in my class."
Q: "Did you fee1 hzppy to work with your peers?"
A: "I understand that it is very human to help one another but I did not feel very
happy because of "political responsibility". Sometimes I felt stress if my peers appeared
to have no improvement."
Doi: "At that time we did not focus on social skills such as oral communication,
self-confidence, and trust building. So I think that in working in groups with case studies
we can not only develop a good understanding the but also develop social skills that our
education system has not taken to be important."
Ky: "I agree with you all."
By comparing the disparity of the two learning activities of different situations, I
believe that the students told the truth about "political atmosphere" they used to have
when learning with their peers ten years ago. They realized that the cooperative learning
in class or in small groups they had just experienced was comfortable. They understood
that these approaches could help them get a deeper understanding of the course and
develop social skills such as trust building, conflict management, and oral communication
too.
Deep understanding of the course
Employed to triangulate other thesis data analysis, the purpose of the interview
was to focus on students' opinions of the course and the teaching approaches to ascertain
whether they could get a deep understmding of the course or not, especially with
reference to the cases,
The students did not that learning with cases was time consuming. In other
courses they had to take nores in class. When they opened these notes at home, they often
felt skeptical about their contents because instructors always lectured too fast so they
hadn't had enough time to note down everything properiy. The students feIt confident
with the case study course. According to them, the case must be interesting and make
them curious to learn more. This case study, the "Pig-Bel", meets that requirement so
they liked to talk beyond their responsibility to simply speak. The students agreed that
they tried to find materials related to the course and the case, and to collect information,
but the university library had very limited sources of science books. From the teaching
approaches, the students found they could learn lots from peers in class and group
discussions, especially in the "debrief' stage. The following excerpt from :he interview
transcript can describe students' thoughts about the case.
Vy: "I have the same thought as Thinh. I do not think the case study is time
consuming. Through the case we can have a general view of the course. I regret that we
won't have a chance to work on a second, and third case. Through the case we gain a
deeper understanding of the course. We tried to get a deeper understanding by ourselves
and we also wanted to learn eagerly from our peers7 discussions or arguments. In class,
usually we preferred being asked to speak rather than volunteering to speak first. In
group, we spoke freely and in the "debrief' and "replay" stage we felt very relaxed and
interested."
Ky: ''I agree with you two very much."
The students concurred that with the lecture available they could use their time to
seek more information from other materials to get a deepcr understanding of the course, to
discuss in class or groups. They believed that the case "Pig-Bel" was interesting for them
and made them more curious about all physiological symptoms. From the case
discussion, the students could get a better understanding not only of the course but also of
other fields such as microbiology7 pathology, and biochemistry.
Competitive spirit
Students had been used to leaming individually and competitively for long time
with traditional teaching and learning so it is very easy to understand why they wanted to
compete with other groups in the "debrief' stage, even though it was just in fun. Here are
some of their ideas about the competitive spirit shows in the "debrief' stage.
Thinh: "...So I think we learned lots from our peers in class and group
discussions, especially with the "debrief' stage. We felt very excited to see our ideas put
down on the blackboard by the teacher and to wait for other groups to do the same. It was
a kind of competitive feeling to see whether our group would be appreciated or not."
Vy: " ... It would be more exciting if in the "replay" stage teacher went to a
conclusion that which groups had the best ideas or right discussions. We can determine
by ourselves but we need teacher's evaluation ..."
The students were looking forward to receiving appraisal from their instructor and
peers. It was very natural because cooperative learning does not mean no rewards or
appraisal. By contrast, as Johnson & Johnson (1984) suggest, bonus points or rewards for
the best group would be appreciated during teaching with cooperative learning in groups.
Johnson & Johnson state:
In addition to an assessment on how well they are leaming assigned concepts and information, groups should also receive feedback on how effectively they collaborated. Some teachers give two grades, one for achievement and one for collaborative behavior. (p. 39)
When presenting their collaborative work the students were expecting to be
evaluated well. They can recognize by themselves how well they performed but an
instructor's evaluation is more highly valued.
Teacher-student relationship
As mentioned in chapter III, I wished to build a close relationship between teacher
and students during teaching with the new approaches. I often listened to students'
speaking, encouraged them to speak out about their ideas. The following excerpt from the
debrief transcript could demonstrate how the students felt about the teacher-student
relationship.
Thinh: "Not only me but almost my friends appreciated this course very much.
We could learn many things from the course itself, from the teacher, and from other
peers. I think that this methods makes us more active at learning."
Vy: "Besides, fortunately you are our instructor. You have a very gentle manner
to encourage us to join class discussions. You often listened to our conversations, you
respected our ideas even when we had with wrong answers so we feel very comfortable to
talk. I am really not sure that other courses could apply these methods because almost all
the instructors in this university are very hard. They would get angry if we had wrong
answers." (laughing).
Huong: '7 think so. Whenever we are asked to answer, we get terrified and we
often lose our confidence, our self-control and we forget everything we want to say."
Doi: "Yes, I agree. So I think it depends very much on the instructor's
personality. I found one more thing very nice in these methods, we students never feel
hurt if we have the wrong answer because instructor never says that this was the right or
wrong answer."
When talking with them the students made an open "comparison" of my manner
and that of other teachers'. I understand that the students just wanted to let me know
about their feelings at school toward the traditional and the new methods of teaching.
They lose their confidence when being asked questions by other teachers but they never
fml bad about those & x h x s ' anger; it is very " c o m n and caturd" ir: student life at
school anyway.
Suggestions for improvements in the content of physiology course
Most North America universities elicit student feedback on courses and instructors
to help improve courses. The feedback I got from course evaluation and from the
interview will be valuable in developing a better physiology course and improving the
teaching methods.
According to the students, every student ought to have course materials available
ahead of time. For industrious students the benefit of advance reading meant this was
their favourite choice. For not-so-diligent students this benefit makes them "lazier".
They did not have to pay for those copies. They did not have to go to class to note the
lecture down. The students proposed that aii of them should have to buy the copy of the
course materials with their own money to make them more responsible for their study.
Actually the university does not demand that students go to school every day. Passing
examinations is considered as the best course evaluation anyway.
The students were really concerned about having the instructor's final conclusions
although they recognized that they could reason on their own. Traditionally speaking, the
teacher's evaluation has been respected and considered more valuable, so the students
wanted every discussion to be clarified by instructor's full explanations or conclusions.
Here are their ideas on this matter:
Doi: "Yes. Actually the instructor did give us many ways to solve the problems.
We also wanted to solve the problems by ourselves but the textbooks and materials
related the course were in such short supply that we could not do that. Sometimes wc got
confused because we did not understand how to reason, or to find the best answer."
Thinh: ''Materials related to the course and the case study are still limited. We
share this diEculty with the rest of the university. If we would have had enough support
from books and lab work we could have had gotten better results with these styles of
teaching and learning."
In terms of examination organization, the students agreed that a midterm
examination was very useful but they preferred a multiple choice exam to a written one.
The midterm examination they took was a bit dificult for them because time was limited
and the students were not used to writing a concise exam using key words. For every
question they wrote a composition with an introduction, body, and conclusion. So it was
hard for them to think carefully and to reason properly to finish the exam well.
According to the students, the course would be better if it included clear pictures,
diagrams or models showing the structures and mechanisms of biological processes,
especially information related to physiology. The students understood that sometimes
they need to use their imagination, but science requires exact information so they also
need exact illustrations too.
The students agreed that in discussion they should not ig~ore social skills but that
also they should not concentrate on these skills so much. They wanted to pay more
attention to the topics under discussion rather than how to discuss it. They were sure that
no one would feel hurt if she or he had a wrong answer.
The students really a~preciated the course because it dealt with daily life, and
particularly with health and disease. But they agreed that the course would be more
interesting if ii included even more information about health and disease. They
recommended I prepare at least three cases for the holistic structure of physiology course
in future.
Course evaluation
There were 81.81 % of students who stated that the course content and methods of
teaching were very good. Their evaluations in detail were as follows:
Good points:
The course was well prepared with organized. clear, and concise content which
helped students to understand the concepts easily.
The methods of teaching motivated students to work harder on the course, to
speak out, and to get a better understanding not only of the course but also of
other aspects of science. Students could grasp the course content through class
and group discussions at school so they spent less time memorizing it at home.
The instructor was always enthusiastic, listened to students' ideas respectfully.
Drawbacks:
0 The course lacked reference materials.
The course should be illustrated with more pictures and diagrams.
The instructor's explanations were really needed to ascertain the right or
wrong concepts.
There were 19.09 % uf students, who also agreed with the above evaluation, felt
they lagged behind the class, and had to do too many mandatory preparations at home
while they had to prepare for other examinations as well.
When teaching the course, my intentional teaching strategy was to avoid judging
students' ideas and arguments, or explaining biology concepts to the students. If the case
needed explanation, I supplied many directions to the students to figure out the problems
by themselves such as using metaphors, information from other materials, etc. I really
wanted the students to think and to reason, and to find their own correct answers. But the
shdents sometimes got confused and appeared to lack the reasoning skil!s perhaps
because they were used to the traditional of learning and teaching. Besides, as they
stated, the shortage of books and materials was the main reason for them to explain why
they needed to have full conclusions and explanations from their instructor.
So I completely agree with students' course evaluation, including both good
points and drawbacks. These comments will be useful to improve the teaching methods
in my future work at Dalat University.
Self-evaluation and midterm examination result
Self-evaluation:
Based on the criteria of participation and course preparations provided, the
students graded themselves with the following results as follows:
Grade A: 7 students (16.60 %)
Grade B: 15 students (35.72 %)
Grade C: 17 students (40.48 %)
Grade D: 3 students (7.2 %)
A combination of self-evaluation and midterm examination result shows that the
students did not evaluate themselves precisely. Let us take a look about the results which
came from students' performance. Students who had good participation could get a 10 %
bonus mark regardless of his or her exam mark.
Midterm examination
Midterm examination result:
Grade A: 13 students (30.95 %)
Grade B: 19 students (45.95 %)
Grade C: 7 students (16.66%)
Grade D: 3 students (7.2 %)
Comparing the results of self-evaluation and the midterm examination, the data
shows that only 17 students (40.47 %) graded themselves precisely. There were 17
students (40.47 %) who self-undergraded themselves and 8 students (19.05 %) who
overgraded themselves.
Undergrading is probably a typical characteristics of Vietnamese students because
humility is valued.
When marking the exam papers I found that students' performance was mainly
based on memorization. There was one question (The functions of gastro-enzymes in
intestinal system) which required students to understand the favourable conditions of'
temperature, pH, etc. suitable for enzymes to activate, but almost 100 % of the students
could not answer precisely. Through the interview, students revealed that the exam time
was a bit short to allow them to think deeply about the questions. I think this fact will
help me set an appropriate time frame for future exams.
Results of the self-evaluation and the midterm examination show how the self-
appraisal and self-esteem of the students developed through the class acti\.ries. I
observed that the students did not welcome the chance to evaluate their own work. They
did not see self-evaluation as a chance to learn more about themselves, as an opportunity
to examine their strengths and weaknesses, and determine where more work was needed.
They seemed afraid to be honest in owning up to where they were having trouble. They
did not see that the ability to look at themselves honestly allowed them to be more open to
learning.
Evaluation has been considered, however, as the teacher's job in Vietnamese
schools. Students think that they can learn more when someone else does the evaluation
for them. Ironically, all of the students who overgraded themselves belonged to the
average and below average acheving students, while the majority of students who
undergraded themselves was belonged to above average and high achieving students.
Aside from humility, maybe these students lacked a good skills in self-evaluation. They
were unable to look at their own work critically. Looking at their work critically would
leave them open to criticism that they would prefer to avoid. So in order to the make self-
evaluation process better and more precisely, the skills of self-evaluation needs to be
taught and practiced for students through learning activities at the university.
Chapter Five
Conclusisns, Limitations and Recommendations
From the research questions to the research results
Returning to the research questions posed in chapter One, I found that the research
results provided some answers.
Research question one: Do student-centered methods with whole-class and
group discussions of STS content change students' attitudes toward learning science,
when they have been under the strong influence of a teacher-centered tradition?
Before taking the course taught with "student-centered" methods the students
indicated a positive answer to this research question through their response to the survey
statement: Biology courses instructed with a combination of theory and real-life
applications by using "student-centered" methods stimulate students to develop positive
attitudes toward learning science. The second year part-time class which I instructed
supported this statement unanimously. After participating in a few classes of the
physiology course, the students stated that the new approaches encouraged them to be
active toward the course and other related fields. They were stimulated to look for more
information from materials outside cf class, to propose more questions and to find more
solutions to share with instructor and peers in class.
Although the majority of students supported the approaches from the course
evaluation, the results were not unanimous (81.81 %); still, it is obvious that the first
research question was answered positively; the subjects did have a positive attitude
toward learning the course instructed with STS content and "student-centerect" teaching
methods.
Research question Two: Do case study teaching methods with cooperative
learning in groups bring about a deeper understanding of the cor$~se and of ather related
subjects?
Before taking the course, the second year part-time students were one of the three
populations who showed the strongest support for the following statement, agreeing with
it unanimously: Class and group discussions in a course using case stuciy with S75
content can help students develop deep understanding of the course and social skills.
After finishing three sections of the physiology course, the students again confirmed their
ideas about the approaches through data collected; through the course evaluation and the
interview. In the course evaluation, there were 81.8 1% of students who agreed that
through seeking more information from other sources, and sharing their experience and
ideas via class and group learning activities, they gained a better understanding of the
course and of other related subjects such as microbiology, and biochemistry. One of the
main themes coded and then analyzed from the interview data was "Deep understanding
about the course" (chapter IV). The students confirmed that they found it interesting in
discussing the "Pig-Bel" case, that they sought more information related to the case and
the course to find out about the mechanism of the disease. They had the chance to
perceive the entire range of physiological symptoms, and to learn more about the disease
in Vietnam through discussion process especially the "debrief' stage.
With support from the data analysis of the interviews, I concluded that the second
research question could be answered positively.
Research question Three: Does discussion-based teaching help students develop
their social skills?
In the survey, statement eight (Social skills such as oral communication, trust
building, and self-confidence need to be taught and practiced) and statement nine (School
should have learning activities to get students involved in being taught and pructiced the
social skills) both concentrated on social skill development. The students from all three
populations showed their strong support (from 92.10 % to 97.30 %) for the importance of
social skill development in education. After experiencing the learning activities, the
students responded to these statements through course evaluation, class and group
discussions which I observed, and interview data, as analyzed in chapter Four.
In course evaluation, 8 1.8 1 % students agreed that the approaches helped students
develop social skills; they wanted to talk, to share and to consider their peers' ideas.
From class discussions and group observations focusing on social skills, it was noted that
the students learned to manage conflicts, developed trust and interpersonal skills, and
communicated ideas. Students showed evidence of the quality of their thought in the oral
communication of their ideas. When they made oral presentations in class, especially in
the "debrief' stage, their language was clear and their views were based in data. They
were able to give legitimate examples from valid sources to support their points of view.
When they spoke, it was easy to understand what they said, to follow their reasoning. In
class discussion there was a tendency for males to speak more frequently than female
students. In contrast, in group discussion, females compensated; males were dominated
by females. After taking the course, and especially the case study as part of the course,
the students recognized that one of the purposes of the case study teaching method was to
focus on social skill development. They stated that while learning through class and
group discussions they felt that they liked to talk, and to share their ideas with peers in
class to get a deeper understanding of the course content.
From the evidence above, it is clear that the research convincingly supports a
positive answer to the third research question, with strong triangulation of the data.
Conclusions
With the positive answers to the research questions having been elicited from the
findings, some basic conclusions can be synthesized as follows:
The biology second, third, and fourth year students at Dalat University had
positive attitudes toward school. They had keen concerns about the content
and teaching methods in biology courses that would develop positive attitudes
toward science, as well as a deeper understanding of science and improved
social skills. The older, and more experienced students were more concerned
with STS content of biology courses, student-centered teaching methods, and
learning activities which develop socials skills at school. These results
suggest that there must be a need for developing appropriate curriculum of
biology courses including STS content with its learning activities.
"Student-centered" methods with whole-class discussions and case study was
confirmed to have helped the students develop a deeper understanding of the
physiology course by developing reasoning, and encouraging students learning
from peers, and seeking more information from other materials. Results
confirmed that, while sharing their ideas with instructor and peers, the
students learned social skills: communication abilities, trust building, conflict
management, and especially individual accountability.
From the observed phenomenon of male-dominated discussion in whole-class
work and female-dominated discussion in group work, it was concluded that
whole class discussion and group work should be both conducted to develop
deep understanding of science and social skills for both ferAe and male
students equally.
Skills of course evduation md self-evaluation need to taught and practiced for
students through learning activities at university.
From research results to generalizability
Trying to implement the new approaches in a traditional environment of teaching
and learning, especially since I nad little experience of or training in case study teaching
and student centered-methods, I realized that this research offered an opportunity for me
to Iearn about my own teaching. While improving my own teaching skills I need to solve
some problem which I will face in my future teaching.
Limited funds for course preparation:
I wonder whether these approaches could be generalized given the shortage of
academic funding. The university is so poor that it can not afford for to hold lab for all
part-time classes; only full-time students can access labs which are funded partly by the
Ministry of Education and mainly by student tuition fees. The physiology course in
which I instructed had no lab component. The idea that "the combination of theory and
reality (including lab work) stimulates students to develop positive attitudes toward
learning science" could not be completely realized in these circ*mstances.
Photocopying costs were also a problem. With the help of CIDA program funds, I
could provide the students enough copies of course materials so that they could prepare
for class at home. Students appreciated the benefits of having copies of these materials.
In future, if budgets did not cover photocopying, the university could ask students to pay
for the costs, as the students interviewed suggested, but their enthusiasm may be reduced
if costs rise too high. In the long-term. the problem could be solved by larger government
budgets for education but under present conditions, lack of funding makes me pessimistic
about the generalizability of these approaches.
Lack of concern from colleagues and faculty
All faculty members did support my research; they provided me whatever 1
needed to make my study work. The Head of Department of Biology was very
approachable, and helped me edit the content of my survey, recommended I work with the
first and second year full-time students, and provided great support. However i felt
uneasy that my colleagues did not show any interest in what I did or what my findings
were. I offered to present my work (in Vietnamese) to the Fxulty but they answered that
they did not need to have my report. They were happy that I could finish my work
punctually. Sometimes 1 felt isolated with the "frivolous" approaches to teaching since
"money carr tell everything", from my colleagues' perspectives I guess. In my own
estimztion, success or failure in education depends very much on funding but teacher
education also depends on time, effort, experience, enthusiasm, and a sense of
responsibility and commitment. Money alone could not solve all problems we face in
education, a human science. What is required is more subtle than money.
Sometimes when teaching the class E saw many students from other classes
standing outside the classroomdoor, watching me and talking about what they saw on thc
blackboard. I wished I could do something more to prove the significance of the new
teaching methods but I found it impossible. I realized that I really needed the concern of
my colleagues and faculty to support me with their own experiences, and I needed to
obtain feedback from them to improve my teaching approaches. I wonder whether, when
I come back to my country to continue my job, the teaching approaches will have a
chance of survival or whether they will be "fatally" isolated because of the strong trend
toward traditional teaching methods.
Lack of patience or tolerance for unexpected situations
f sometimes k a m e confused and disappointed because of unexpected situations
that almost made me lose my temper. I understand that it is not a good idea to blame
students or to be "aggressive" with them. I did confront students on two occasions: one
was the day almost all students stayed at home to prepare for an exam in another course,
and the other was when I teaching chapter 11, on the circulation system. In the former
case, I was frustrated and embarrassed because of the presence of my two colleagues.
The students did not apprise me of their absence ahead of time although I had promised
them in the first class that I would let them know at least two days in advance if I needed
to cancel the class, and I expected the same from them. I had controlled myself to some
degree but E felt really upset afterwards. These feelings discouraged me for a while
although some members of the class met me on my way going home and apologized to
me for what they had done. The second incident happened when the class was so inactive
that none of the students wanted to concentrate on the course. They were so worried
about exam results from other courses that a depressed atmosphere was created in the
classroom. I tried to switch from a "student-centered" method LO a teacher-centered
method to adapt to the class mood, students kept silent until break time and then rushed
out of the class as if they had been suffered a painful duty. I have learnt to be more *
flexible and deal with my own distraught feelings. I need to train myself to have more I
$ 5 ' tolerance for dealing with unexpected situations in order to make the class atmosphere
more active, and productive.
Preparation of course and ather materials
Within very short time I prepared the course in Vietnamese. The cost of
photocopying was a big concern and materials from the university library were too scarce
to meet class needs. I agree with the students that the course lacked infomation from
O+ar , ,, s,;,,,s, *. CI\P ad &be eot.me mateiid itself iacked illusi~aiions arid diagrams. I know that
I could have done better to prepare the course but I had limited funding and time.
Nevehless , I felt uneasy hou&ut my teaching. Fortunately, the students could share
their experiences and they helped me to make the course work. In my future teaching,
such problems must be avoided. Good preparation of the cortrse and other materials
ought to result in better "student-centered" methods of teaching with cases.
Flexibility in instructing methods
Before applying the approaches, I read about how to develop good questions thilt
build habits of thinking in students. I was sure that good questions would be framed in a
way that encouraged thoughtful examination; the questions would invite students to think,
and to reason rather than demanding from them a pat answer. In order to avoid a forced
choice betwsen "yes" and "no" I overused the facile "why" instead. The students became
"exhausted" and I sometimes ovenvhelmed the students with too many why questions.
Unfortunately I realized this near the end of my teaching. The students deserved a more
flexible atmosphere and more open questions.
Limitations of the research
Some problems and limitations of the study defied easy solution.
Research time was limited. The research took place over only 4 weeks (one
week for doing the two surveys, and three weeks for teaching and interview)
so it was impossible to check the results by repeated observations or interview
cross-examination. The limitation resdtcd in a weak validity, reliability and
generalizability for the study.
Subjects were not hom*ogeneous: the 42 part-time students differed from one
another in terms of age, experience, background knowledge, salary, marital
status, etc. This may affect the generalizability of the research, especially in
terns of hH-time classes.
Using one case and dealing with a shortage of reference books and materials
made the course less effective &an expected.
The transcript of the group discussion on the case "the Pig-Bel" was based
mainly on student observers. 1 could observe only group one from the
beginning to the end and the video taping of the other three groups was
discontinuous. So the data from grotip work with case study was somewhat
limited.
Data analysis process concentrated only on descriptive analysis rather than
going deep into details of the phenomena or psychological aspects of the
students h a u s e research time was short. Replication of the research was
impossible, resulting in a poorer consistency of analysis.
By a "strange" coincidence the students who voluntarily participated in the
interview were all high performance students so the interview lacks data from
lower performance students, resulting in a biased analysis.
Recommendations for application
I suggested that, although Dalat University remains poorly equipped in terms of
tex:bwks a d lab equipaent, the physiology course could be taught in ways would help it
approach international standards.
The course content should be supplemented with more pictures and diagrams
related to physiological structures and processes to help students grasp the
concepts.
The course should focus more on the mechanisms of physiological processes
and on information about health and diseases.
The course is best taught using the case study method involving at least three
cases with students iavolved in group work.
The course can provide students with opportunities to think and to reason,
although so~lretimes instructor's explanations and conclusions are needed to
compensate for the shoaage of textbooks, materiais, and lab work.
Overuse of "Why" questions should be avoided in class discussions.
Questions should not be too abstract, too general, ambiguous, or leading; they
must be clear and invite students to think, and speak out about their ideas.
0 Aside from giving bonus points for participation, encouragement can be given
by awarding a prize to the best group.
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Appendix A
Survey of Students' Perspectives Toward School
Please circle the appropriate number on the right which most closely corresponds to your
feeling about the statement on the left.
1 2 3
Agree Disagree No opinion
1. Regardless of the basic training program of
Dalat University, the contents of biology courses
should not be concrete and pure science.
2. Biological courses' contents should consist of STS
(Science-Technology-Society) information.
3. Biology courses instructed with a combination of
theory and real-life applications stimulate students to develop
positive attitudes toward science.
4. Class and group discussions of the course through
case study with STS content can help students develop a
deep understanding of science and social skills.
5. During giving lectures instructors should propose
questions related to background knowledge
and encourage students to answer.
6. Regardless of iheir levels of performance students could
learn many things from peers at school.
7. High performance students should concern and help low
performance students with their study.
8. Social skills such as oral communication, trust building,
and self-confidence need to be taught and practiced.
9. School should have some learning activities to get
students involved in learning and practiced social skills.
10. The performance and success of students in the
workplace after graduating will depend very much not
only on their qualifications but also on their social skills.
Appendix B
Interview Questions
(Interviewees are students)
Question # 1 : How did you feel when attending classes that used the new teaching
methods?
Question # 2 : Before 1985 we had a form of cooperative learning in groups, and now
we are working cooperatively. How do you see the differences and
similarities of the two learning activities?
Question # 3: What are the good points of these new teaching methods?
Questions # 4: What drawbacks do you see in these methods?
Question # 5: What are your suggestions for improving the curriculum and teaching
methods?
Question # 6: While taking the course how did you feel about the presence of:
a) the video camera
b) the tape recorder
c) noises from other groups
Question #7: Your opinions about your group:
a) Was the group the right size?
b) Did the group function well?
c) Did you or anyone in the group monitor the group's performance ?
d) Did you feel uncomfortable when you dominated other's ideas
or, by contrast, someone dominated yours?
Question g8: Were the cases:
a) time consuming?
b) chances to read materials and get a deep understanding of the subject'?
c) chances to hear others' ideas?
d) chances to collect materials and write down 'big ideas'?
Question # 9: What you like to be taught for the rest the course:
a) Continue with cooperative learning in groups for lab
b) Continue the course with case study and cooperative learning in groups
c) Turn back to the traditional methods of teaching and learning
d) Keep teaching the course with pure science only
Appendix C
The "Pig-Bel"
(A summary of "The Beast in the Belly", by Sherwin (1995)
Not long ago a 24-year old woman named Grace Lopat registered for assignment
as a substitute teacher in the elementary school system of a small town outside New
Haven, Connecticut. Although Grace walks nowadays with a barely perceptible shuffle,
in all other ways she presents the perfect image of vibrant good health. It comes as no
surprise, for example, to learn that she placed third in a country pageant a few years ago.
Even forewarned with the knowledge that since the age of eight she has required twice-
daily insulin injections to control her diabetes, anyone meeting Grace would have good
reason to see her in the personification of that idealized image of a past generation's
sketchers and artists, the American Girl. Certainly it is a great deal easier to think of her
as a wholesome, smiling beauty contestant than it is to imagine her mottled and swollen,
in a delirium of fever and near death, being rapidlv wheeled towards an operating room
one spring afternoon four years ago. She had bee assessed a Class 5 risk for anesthesia,
in the opinion of every physician who saw her. To this day, she's not sure whether to
credit her survival to the flabbergasting marvels of modern scientific medicine or the
spiritual intervention of her long-dead father, and a few of her doctors sometimes wonder.
Either way, it took a miracle to save her life.
The American Society of Anesthesiologists describes a person in Class 5 as "a
moribund patient who is not expected to survive without operation." No one, doctor or
otherwise, seeing Grace Lopat just before those preoperative moments had reason to
dispute that description, and most observers would have projected her survival period to
be hours rather than days. I was her surgeon, and I have now had four years to think
about it. I am absolutely convinced that I have never taken a sicker patient to the
aperating rmm, everi if i include in my recollections those few who did not leave it alive.
The reason for Grace's survival is no easier to pin down than is the origin of her
sudden catastrophic illness. Although our clinical team was later able to trace the details
of the process that made her so sick, we are still puzzled by the "why" of it. We know the
culprit but have no idea how it managed to get as far as it did. Even the instructions we
gave Grace after her recovery were based on guesswork: She was told never to eat pork
again. The injunction had no scientific basic. In fact, it was nothing more than a kind of
clinical rabbit's foot that none of us were willing to throw away, probably because it was
the only one piece of advice we could think of. Grace never shared our concerns; I
recently discovered that she eats pork whenever she can.
Actually, the amount of pig meat consumed by our patient in the day before the
onset of her illness was not enough to indict it. She'd had a Chinese dinner about 40 hours
before her first symptoms, and it included pork fried rice and spareribs. Other than that,
she has no recollection of having eaten anything at all different from her usual fare.
Grace's medical saga began in May, on the Monday of final-exam week at the
state university where she was completing her sophom*ore year as an education major.
She has just taken the performance exam for a dance course in which she 'd been enrolled
that semester. It was about three o'clock in the afternoon, and she was walking across the
campus, feeling pleased with how well she 'd done and thinking about the coming series
of finals.
"All of a sudden, I was on the ground, I couldn't imagine how I got there. I got up
quickly because of course there were thousands of people around the campus, and I was
thinking, 'Dear God, I hope no one saw me fall.' I looked around and there were no
stones, no sticks, no cracks in the sidewalk, ?here was absolutely nothing that I could
possibly have tripped on. It was my legs gave out, and I thought it must have been
because I 'd just danced for an hour. My roommates said later that I was such an idiot I
must have tripped over my own two feet"
On the following moling Grace awoke feeling sick.
T was vox&iig, I u.zf mniing tr, the bathroom with diarrhez, and 1 was sweating,
I thought, 'Oh great, I caught some kind of a grippe, some kind of a flu. I went back to
bed, but I kept going in and out of it. Finally, my roommates began to get worried
because there had been several times in the past when I got dehydrated and had to go to
the hospital because my diabetes went out of control. But when I tested my sugar, it
wasn't any higher than usual.
"Finally, the girts started to get scared. They called my mother at work, and she
took rr.e home. 1 drank lots of diet ginger ale the rest of the day and used suppositories to
stop vomiting. That whole night I was dizzy and throwing up, and drinking water and
vomiting again. By early the next morning, my abdomen was aching and I couldn't feel
my arms and legs. I tried flapping my arms around and I still couldn't feel them. No
matter how weak I'd been in the past, nothing like that ever happened before. I was in
hysterics, it was like a nightmare."
Anne Lopat, Grace's mother, has been teaching elementary school for more than
twenty years. After her husband, Bill, died suddenly oi a coronary when her only child
was ten, Anne became not only the small family's so!e breadwinner but Grace's entire
support system. After Grace's juvenile diabeteq was diagcosed in 1978, Anne took it on
herself to learn all she could about the disease, and to become something of an expert in
the various ways it manifested itself in Grace. Her job wasn't always easy. Like most
diabetic kids, Grace had a way of breaking the rules, and it sometimes took all of Anne's
accumulated diabetic wisdom to extricate her child from the consequences. Occasionally
her efforts failed, and it would then be necessary to rush the dehydrated girl down to the
Yale-New Haven Hospital emergency room. Over the years, actual admission had been
necessary seven times, always to treat acidosis, the rapid buildup of metabolic products in
the blood of diabetics, which can lead to air hunger, coma, and finally, if not reversed,
death. The last admission had been only six weeks earlier.
But knowledgeable as Anne was about the way Grace's diabetes behaved, on that
May morning she found herself facing an entirely new symptom. "When she woke me at
about 5:30 and said she couldn't feel her arms and legs, I knew f had to get her down to
the hospital rigbt away. W e 1' was helping her to the car, she told me she couidn't even
feel that she was touching the ground."
There was no prolonged wait in the emergency room when the Lopats signed in at
6: 19. As Grace recently told me, ''Generally, you can come in holding your head in your
hands and they tell you to wait. But when you are a diabetic, they take you right away."
Blood samples were drawn and intravenous fluids were started without delay.
About an hour and a half after arrival, Grace was told that her test results seemed
reasonably satisfactory. But she couldn't be reassured, and she began to feel herself
become increasingly panicky. Soon she was shouting.
"Nothing felt right. At that point, the doctor and nurses were changing shifts, and
no one was paying any attention to this screaming person. 1 was yelling, 'Won't someone
listen to me? There's something wrong!' My abdomen really, really hurt, like it was a
tight, tight muscle spasm and everything was all squeezed together. That frightened me,
but I tried to blame it on the 24 hours of vomiting. But what really scared me was that !
had no body perception. I didn't feel like I was there. It was that same feeling I've had
when I've had a tooth filled and been given gas. It's like I have no body at all.
"My mother kept talking to me all the time, trying to calm me down because I was
yelling and thrashing around. And then she asked me if I knew I was going to the
bathroom, I didn't. Then I heard her yell, "My God, it's blood!' and thcn she began
calling out, 'Nurse, Nurse!' The nurse came right away, and after that my only perception
was dribs and drabs of the faces of the doctors and nurses around me."
In f x t , Grace's blood tests had not been normal at all. The most striking
abnormalities were a markedly elevated white blood cell count of 28,500 per cubic
milliliter (the normal level is about 5,000 to 10,000) and what is called a shift to the left,
which refers to a large increase in the number of mature and immature granulocytes, cell
that increase in number when an acute infection must be fought off. At 654 milligrams
per deciliter, the blood sugar was elevated to some sewn times its normal value, arid a
moderate degree of acidosis was present. The entire picture was characteristic of the
abnormalities that rapidly appear when a diabetic develops serious infection, Once the
proper cultures had been taken, the emergency room physicians started Grace on several
inuavenous antibiotics.
most unusual aspect, of tbie bid smdies wk5 the extremely high white cell
count, which was approximately twice what might be expected in the ordinary kind of
infection. But far more worrisome than the laboratory results was Grace appearance. She
was throwing herself around the gtuney and shouting for help without seeming to be
completely aware of what she was doing or that she had just passed half a pint of bloody
tmf - The k i n of her entire body had kcome mo?t!ed, with great purple-gray blotches
appearing everywhere, separated from mother by small patches of stark whiteness. Her
body temperature was a full degree below normal and her blood pressure was beginning
to fall. The entire sequence of event added up to the clinical picture of a sepsis, a massive
bloodsiream infection that leads rapidly to inadequacy of the circulation, often followed
by organ failure and then death.
On the presumption that the bloody stool and abdominal pain might be clues to
finding the infected site from which the bacteria were being hurled into the circulation,
the resident physicians sought consultation with Suzanne Lagarde, a gastroenterologist on
the hospital staff. When they phoned the patient's physician, Murray Brodoof, to tell him
their pian, he said he wouid also contact a surgeon, on the chance that some remediable
intra-abdominal event might be the cause of his patient's strange symptoms. I was
draping a middle-aged man for a hernia repair when Brodoof s message reached me.
Because I was decked out in a sterile regalia, the nurse held the phone to my ear, and
Brodoof described what he had been told. I was committed to the operation about to
begin, so I had the nurse page the resident on my surgical service, and I delayed the
operation just !ong enough to ask him to go directly to the intensive care unit, to which
Grace had by then been transferred.
Sue Lagarde is a slight' bespectacled woman in her late thirties whose stylish good
taste iri clothes seems pleasantly incongruous with her studious face. She is a skilled
clinician, and so enthusiastic about her work that she approaches diagnosis with a certain
cheerful ebullience, manifested most directly by a rapid verbal delivery in which the
words tumble out so closely on one anot_fier that she seems always on the verge of
stuttering. When Lngarde examined Grace, she saw a young woman with what she called
5 hysterical personality throwing herself around the intensive care unit bed, complaining
loudly and sometimes incoherently of diffuse body pain. The girl's was cold and broken
out with bfotchiness ductors call livedo reticdark. Although she shouted bitterly and
above all about belly pain, there was no abdominal tenderness and only a mild degree of
distension the rime of Lagarde's examinatitm
Of all the confusing, indeterminate findings, the most disquieting was the acidosis,
it was worsening in spiie of vigcrous treatment. Whatever the obscure nature of ihe
disease process might prove to be, it was obvious to Lagarde that she was dealing with a
desperately ill young woman whose condition was deteriorating rapidly. The situation
was not only dire, it defied diagnosis. Lagarde recommended what she called a fishing
expedition, including a CT scan and a neurological consultation to help point out the
proper diagnostic direction. Unless some sense could be made of Grace's bewildering set
of symptoms, she would soon reach a point beyond retrieval.
By that time I was completing the hernia repair. As soon as the dressing was
applied, I paged the surgical resident. He responded in less than a minute and assured me
that the young woman had no "surgical problem." His examination of he1 abdomen, he
said, was without findings that might suggested the need for operation. "She's hysterical
kid," he said, "and whatever she got is medical, not surgical. You don't have to see her."
He went on to describe Grace's bizarre behavior, her blotchy skin, and the laboratory
findings. It was clear that he was a bit irritated at being asked to consult on a patient who
so obviously didn't need to be seen by a surgeon.
I stopped by the waiting room to have a few words with my patient's wife, and
then headed up to the medical intensive care unit. One of the nurses quickly briefed me
on Grace's condition; though it already been very bad when Lagarde examined her a short
time earlier, it was now worsening rapidly. Despite the attempted clinical detachment of
the nurse's description, it tvas obvious that she was upset, even distraught. The best
intensive care nurses never do become inured to the daily tragedies they witness, and
helplessness in the face of imminent catastrophe, especially when it involves a patient not
much younger than oneself, is unbearable even for the most stoic of professional
personnel.
After our brief discussion, I sat down with Grace's chart to run a quick eye over
the lab reports and the previous medical and nursing notes. As I scanned the three pages
of neurology consultation, my eyes caught the word hysterical, this time used to explain
the arm and leg symptoms, which fit into no clinical pattern that made sense, The overall
impression of the neurologist was that the patient's symptoms were the effects of diabetic
acidosis. His final recommendation was: "Suggest close clinical observation. Consider
L-S (lumbosacral) CT if symptom persist."
On the next page I found the surgical resident's note, describing his findings. At
the end, under Impression and Plan, he had written, "Benign abdomen in setting of acute
neurological event and GI bleeding suggest vasculitis (underlining his) though sepsis
possible ... possibly meningococcus. No evidence for acute abdominal process."
There was a tone of finality in the note. Even the customary concluding words of the
surgical consultation, "Will follow," were absent. In their place was "Will speak with Dr.
Nuland." I stood for a moment at the entrance to the class-enclosed cubicle where Grace
lay attached to electronic monitors, a nasal oxygen line, and a tangle of intravenous
tubing. As I observed her from the foot of the bed, I asked the nurse to pull the sheets
away so that I might look at the patient's entire body from that perspective. Even to me, a
case-hardened veteran of other people's affliction, the exposed sight was harrowing. The
mottled object on the bed looked like a bloated corpse somehow preternaturally animated
by the terror of yielding to eternal stillness. Its thrusting chest was straining up and down
like a perverse bellows sucking air into itself, while the head and all four extremities were
flinging about in a frenzy of attempted escape. In the glare of brilliant MICU
illumination, the skin looked almost eerie. Although 1 had been told of the livedo
reticularis, I was unprepared to see the depth or extent of the large violaceous bursts,
especially as they were so harshly revealed by the many foot-candles of piercing light.
The pattern of blotch and pallor involved every visible inch of body and was much deeper
in its purplishness than ! had ever encountered, except on the freshly dead. The thing's
leg were quite swollen from the knee downward, and even its face had become puffy.
Almost paradoxically, the swelling of the lids made the open frightened eyes seem to
bulge, very like, the tissue behind them was also swollen.
The abdomen was so distended that it partially obscured my view of the heaving
rib cage. In answer to my question, the nurse said that the abdominal girth had reached its
grossly protuberant size over the previous two hours. When I stepped to the bedside and
tapped on the belly in the diagnostic maneuver called percussion, the amphoric boornlet
of resonance that filled small cubicle had the pitch that might be produced by a felt
hammer hitting a kettledrum. With good reason, clinicians call such a note tympanitic.
Grace's tympanitic abdomen told me her intestines were blown up with gas, and the
absence of gurgles when I listened through my stethoscope meant there was no peristalsis,
no rhythmic contractions that normally push along the intestine's contents. When I
pressed down, as gently as I could, into the abdomen surface, the grimace on Grace's
puffy face let me know I was hurting her. She had stopped speaking some time earlier,
but her bulging, uncomprehending eyes stared fearfully at me.
When an abdomen is expanded by a large volume of gas in a short period of time,
it rises like an over-yeasted loaf of bread. Years ago clinicians used the word meteorism
to refer to this rapid belly ballooning, which is encountered only in unusual
circ*mstances. What it means, almost always, is a belly with dead bowel in it. In my
clinical experience, almost no other acute abdominal disease will raise the white count as
high as intestine does when it is in the process of dying. A drastically risen white count in
a patient with a drastically risen belly is a surgical call to action. Unless some thing is
done quickly, the patient will not survive.
The presence of dead bowel furnished a logical explanation for Grace's sepsis and
also explained why all the vigorous measures being applied were not resulting in any
improvement in her acidosis. As long as a major source of infection remains untreated,
there is no way to stop the process of decline. Obviously, Grace needed an operation
soon.
As I was quickly writing my consultation note, Mike Bennick walked hurriedly
into MICU. -Mike is an intense, fastpaced young gastroentologist who had trained with
Sue Lagarde and was now her associate in practice. He hadn't seen Grace before, but
Lagarde had described her condition to him. He instantly recognized how much had
changed since his partner's examination of a few hours earlier and concurred that
immediate operation was mzndatcry.
Bennick and I went out to speak to our patient's mother. We found Ane Lopat
standing with her two aunts and an uncle, just outside the door of MICU. Bennick had
recently treated Anne's mother, and he knew that she would have confidence in his
recommendations. He also knew that this very forthright woman, frightened though she
was, would be impatient with explanations redolent of chart jargon, or with any hint of
evasiveness. As I would increasingly come to appreciate during the next few weeks, she
wanted the truth flat out, and Bennick now gave it to her as directly as possible, softening
the harshness of his message by the gentle tone in which he delivered it: "Anne, Grace is
dying, and we don't know why. We have to look inside it's her only chance."
Anne is a large woman, not only tall but roundly and firmly heavy. Even when
she distressed, there is a stolidity and determination about her. She listened to me
carefully, and her face revealed nothing. She kept her gaze fixed on me, and when she
occasionally blinked, it was done very slowly, as though she were momentarily closing
her eyes to keep her thoughts from being observed. She seemed by force of will to be
separating herself from anxiety in order to focus her mind's entire attention on each
successive detail of what she was being told. She never looked away, even when I
concluded by telling her that the operation would kill her daughter if we were wrong, if
no source of sepsis was found in Grace's abdominal cavity. When she had heard me out,
she simply nodded, and the slight downward motion of her head punctuated my final
words with a full stop. Then she said, "Please operate right away."
I called the OR and asked for the next available room. Within minutes an
anesthesiologist was at Grace's bedside, trying to determine whether she was already too
far gone to tolerate his gases and drugs. The last paragraph of his scrawled consultation
note summarized the pessimism we all felt: "Class 5. Critically ill, undergoing
resuscitation, insulin, fluids, oxygen. Plan rapid sequence incubation. Patient has poor
prognosis, heroic measure to attempt to save life."
Grace was having few lucid moments by then, but she clearly remembers the brief
period when she was in the holding area just before being wheeled in for the surgery. She
was still thrashing about and trying to find some comfortable position on the gurney.
"I wanted to be on my side because I was thinking, "I'm going to die , I'm 20
years old, =d I'm going to die." A priest came and was praying. He was making the sign
of the cross, and I thought, "Oh my God, this is the last rites," that's a sure sign that
you're on your way, you know. I began to say that to my mother, and she was crying, so
were my uncle and my aunts, and they were trying to tell me I'd be okay, even though
they were crying.
"I believe in the power of God, and I've always had some kind of relationship
with my father even though he's not here on earth, I feel his presence all the time, und I
know when he's there. My uncle passed away when I was five. I've always believed my
father and my uncle Ron are in heaven. I've also believed his parents greeted him in
heaven. To me, that meant there's something good out there, and that his parents came to
him. So I was lying there, and I felt my body was being pulled. You know, when you
vacuum a rug and you put your hand over the open hose to be sure the suction's working,
and you feel that pull, it felt like my whole body was being pulled forward. I thought,
'Here I come, this is it, I'm dying."
"And then I saw my faiher and my uncle. They were just standing there, and I was
thinking, 'Okay, God, I'm dead.' There weren't lights, I think you have to go all the ways
to get the lights. Well, I really believed that either they came to me or I came to them,
and my mother tells me I was saying, 'Bill, Ron!' Of course, I never called my father Bill
and I never called my uncle Ron when they were alive, which makes me think things
must be different in the afterlife. But I did say, 'Bill, Ron,' and my father put up his hand
in front of him, and he said, 'No, not yet.' And he sat back. And then I looked up my
mother and said, 'I'm going to live,' and those were the last words I said."
True to their plan, the anesthesia team got Grace to sleep very rapidly. With the
surgical resident and a medical student assisting me , I made a long up and down incision
in the middle line of Grace's very distended abdomen. As I opened the innermost layer,
the peritoneum, a gust of malodorous yellowish fluid poured out onto the drapes. When
we had finished sucking it into several trap bottles, the nurse told us it amounted to some
six pints. With Grace positioned on her back, the gas-filIed gut had been floating on top
of the fluid, explaning the drurnlike resonance produced by percussion.
We inspected the small bowel. Although most of it was alive, there was a length
of about 15 inches near its origin that was either dead or barely viable. It was suffused
with a dusky bluish hue and was completely without peristalsis, even when I tried to
stimulate it into some kind of action. The discoloration gradually faded out at the upper
and the lower margins of the involved segment, so that there was no definite line of
de~narcation between healthy and sick tissue. The vessels entering the darkened piece
looked normal, and the arteries pulsated vibrantly. When the electronic listening device
called the Doppler was applied, we heard the healthy whooshing sound of good
circulation. And yet the bowel looked asphyxiated.
I explored every portion of the abdominal cavity, seeking an instigating factor for
the imminent intestinal gangrene, but when I had concluded my probing peering, I knew
no more than I had at the outset. No obvious cause revealed itself that might explain the
rapid death of an otherwise normal-appearing length of intestine in a youthful, pristine-
looking abdominal cavity. The gut's blood supply appeared perfect, there were no
adhesions or similar fibrous bands that have might pinched off the involved segment, and
the bowel wall seemed free or' inherent pathology, nevertheless, it was near death. In a
sentence of the operative note I dictated shortly after the conclusion of the surgery: "It is
very difficult to know the cause of this ischemic (lack of blood) pattern, which is of a
form that no member of the operating team has seen before."
I fired a surgical stapler across the intestine an inch above and then an inch below
the dying segment, divided its blood supply, removed the specimen, and handed it off to
the pathology resident, whom I had summoned to the OR on the slim chance that he could
add something of value. He looked at the piece of gut, made a few cuts into it, and
pronounced himself as stymied as we were.
As soon as I was satisfied that we had made a good reconstruction of the gut and
its blood supply, we poured at least ten quarts of warmed antibiotic-laced saline into our
patient's gaping abdomen, in order to rinse out as much bacterial and other debris as
possible. We sucked it clean and ascertained that we had stopped any oozing of blood.
Then we removed all sponges and instruments and began to close. I passed a heavy
polypropylene stitch through all iayers under the skin of the topmost part of the incision,
and then whipped it quickly all the way down the length of the wound until 1 reached the
bottom. I stepped back from the table, and the resident placed a row of some 30 staples
into the skin. Not until one of the nurses began untying my gown did I realized that I was
exhausted.
I went out to the waiting room to tell Anne that the operation had gone well, at
least from the technical point of view. Grace was still septic and not much further from
death than she had been when we wheeled her into the OR suite. Anne asked the obvio~s
question, and I had no answer for it. "No," I said, "we have no idea why this happened to
her intestine. Maybe the pathologist will be able to tell us, after he puts it under the
microscope."
The specimen I had handed to the pathology resident had the appearance of ii
segment of organ that had lost its blood supply, and yet I knew that the flow into it was
normal right up to the very wall of the gut. I expected the explanation to be found in the
microscopic vessels that traverse the bowel wall. I received a phone call from Brian
West, the pathologist in our hospital whose specialty is diseases of gastrointesting '1 I truct.
"Do you have a minute to come over the lab?" he asked and there was a hint af
expectant promise in his rising rhythm that told me it would be well worth my while to
get there right away. The words weren't said with any sense of urgency but more in the
tone he might have used to invite me in for a pint of some long-awaited brew just arrived.
"I want to show you what I've found in the specimen you sent me yesterday."
Anticipating his discovery, I burst in before he could continue: "What do the microscopic
vessels look like?" His answer surprised me. "The vessels are fine. What I think she has
is enteritis necroticans, the thing they call Pig Bel." "Okay, Brian, what's that?" He gave
me a brief explanation, but it wasn't until I got down to lab a few minutes later that I
really began to understand what he was talking about.
Peering down the twin barrels of West's microscope, I could see that all the entire
mucosa, the inner lining, of the specimen was dead, although most of the main layer of
encircling muscle, called the muscularis propria, was still within the definition of being
viable. The most striking structures on the slide were thousands upon thousands of rod-
shaped bacteria forming a lengthy rank along the surface of the mucosa, palisaded like an
irizgiilar picket line of soldiers standing at attention. Their appearance and lab tests
showed that they were a genus of bacillus called Clostridium, closely related to the
organisms that cause tetanus and grts gangrene. In fact, microscopic gas-filled spaces
were visible within the layers of the bowel wall. The toxins produced by these particular
microbes are capable of causing inflammation and necrosis (death and decay) of intestine
wall, hence the process is called enteritis necroticans. Grace's sepsis was caused by the
clostridia, and all the bowel, neurological, and skin symptoms were the result of the
bacterium and its toxins.
By this time I knew that Grace had begun to exhibit various signs indicating
destruction of the cells of some of her voluntary muscle tissue, a process called
rhabdomyolysis. This too was attributable to the toxins. The combination of massive
clostridial growth in her intestine, sepsis, rhabdomyolysis, and the resultant diabetic chaos
were the explanation for entire spectrum of destructive events that our patient had been
experiencing. We could only hope that the removal of the nonviable bowel and the
consequent diminution in the volume of bacteria load would enable our antibiotic and
other treatments to reverse the process.
Clostridia in moderate numbers are normal inhabitants of the gut. Ordinarily they
live in harmony with other bowel organisms and with the various physiological
substances with which they come into contact. Unless some events occur to disrupt the
balance among the gut's organisms and chemicals, the clostridia do not become
sufficiently numerous to be source of danger. For those of us involved in Grace's care,
the clinical challenge was to pull her through; but the intellectual challenge was now to
figure out what had so upset the intestinal homeostasis that a massive overgrowth of
clostridia occurred. For this, Brian West didn't have a definitive answer, but he had
identified a disease model that so closely resembled Grace's that I was persuaded they
were one and the same. Within a few days, and especially after West's diagnosis was
confirmed by an expert in Southampton, England, the evidence had become inescapable.
It's not easy to tell the mother of an attractive young American Girl that her
daughter has a disease whose name is pidgin English for "pig belly," but no more likely
diagnosis has appeared in the four years since Grace's narrow escape. Except for the
csmpiications added by diabetes, the microscopic appearance of the excised tissues are
exactly the same as they are in the thousands of New Guinea tribespeople who have die
of the same process. Acute "Pig-Bel" is a major cause of premature death in the
highlands of Papua New Guinea, with a mortality rate among those contracting the
disease of almost 85 percent. Second only to respiratory disease, it is a leading killer of
children in the area. Its prevalence is highest at times of the year when ceremonial pig
feasting takes place, and the disease has been so carefully studied that it is possible to
describe its evolution with considerable certainty.
The pig feast is an integral part of many of the ceremonials attached to various
kinds of highland celebrations and sacrifices. The meal is always prepared in a traditional
manner. After the animals are clubbed to death, their intestines are removed, washed, and
wrapped in leaves. Alternating layers of filleted carcass, guts, fern fronds, banana leaves,
and breadfruit are placed into earth pits along with sweet potatoes or bananas, chopped
greens, and stones that have been preheated. Tier by tier, a mound of the ingredients is
fashioned, with insulation provided by a final packing of pig's quarter and flanks. After a
large quantity of water is poured into the vapory, structured mass, more leaves and an
outer layer cf earth are added as a covering. In this way, a large steam oven is created
whose internal mean temperature, when visiting health officers have tested it, has been
172 degrees Fahrenheit.
Not only does such a heating system result in inadequate cooking of the meat, it
also provides plenty of opportunity for bacterial contamination. After all the service
cooking is completed, the banquet takes place under conditions that would throw a
sanitation inspector into fits of apoplectic convulsion. Those conditions are ideal for the
proliferation of dangerous organisms, particular clostridia.
Ordinarily much of the clostridial toxin would be destroyed in the body by an
enzyme called trypsin, to which it is very sensitive. Unfortunately, sweet potatoes contain
a chemical that inhipits the action of trypsin, and sweet potatoes are not only a major
constituent of pig feast but also a staple of the highland diet. The ingestion of large
amounts of clostridia-rich meat accompanied by plentiful doses of trypsin inhibitor
provide the perfect concoction to induce fulminating outbreaks of "Pig-Bel". The
situation is made even more egregious by the common presence in local children of the
intestinal roundworm Ascaris lumbricoides, a parasite that secretes its own brand of
trypin inhibitor, adding to what is already in the poisoned food.
As for the clinical aspects of the disease, they are precisely those that were
exhibited some 10,000 miles away in New Haven, Connecticut, by Grace Lopat, minus
of course the components attributable to diabetes.
If massive overgrowth of cfostridia is the cause of enteritis necroticans, the disease
might be expected to occur in places other than Papua New Guinea, and without the
necessity for ingesting a witches' brew quite so potent as the one cooked up during pig
feasting. This is in fact the case. An epidemic disease of identical nature made its
appearance in northern Germany shortly after World war II. It was called Darmbrand, or
fire bowels, and the doctors who studied it concluded that it was caused by unaccustomed
intake of excessive amount of protein-rich food by a malnourished population. Outbreaks
of the same thing have been rep~rted sporadically in several African countries, China,
Bangladesh, the Solomon islands, and at an evacuation site for Khmer children in
Thailand.
A contributing factor in such areas is that chronically undernourished people do
not ingest enough protein to make sufficient quantities of trypsin. When access to meat is
suddenly provided, the meal may for one reason or another be contaminated, and then the
level of clostridial toxin become very high in the body of people with not enough trypsin
to counteract it. This is consistent with an observation made by several of the first
investigators of Darmbrand, which was that it seemed to have made its appearance when
the diet was suddenly changed. The German patients were indeed chronically
malnourished during the terminal phases of the war and for an extended period afterward.
Those who became sick had very likely overeaten on occasions when meat, perhaps
contaminated, was made available to them.
Although there have been scattered reports of individual patients dying of enteritis
necroticans in prosperous Western countries, no real epidemics have occurred among
populations living in areas where sanitation levels are high. But a few single cases are
instructive because they iiiustrate some of the most dramatic aspects of the disease. In
1983, for example, a surgeon and a pathologist at England's Royal Liverpool Hospital
described in the Jomd (the B&sh tend to be quite direct in their medical te&&,gy,
and this is the name of kir most highly regarded gastroenterology journal) the case of a
23-year old photographer's model who walked into their hospital's emergency room at
eight o'clock one Sunday morning complaining of abdominal pain and bloating. She told
the staff doctor that she ordinarily tried to remain very thin but periodically went on an
eating binge. Between midnight and four that morning she had eaten the following: 2
pounds of kidney, 1 and a half pounds of partly cooked liver, 1/2 pound of steak, 2 eggs,
1/2 pound of cheese, 2 large slices of bread, 1 whole cauliflower, 1 pound of mushrooms,
2 pounds of carrots, 10 peaches, 4 pears, 2 apples, 4 bananas, 2 pounds of plums. and two
pounds of grapes. She had then gone to sleep for a few hours and been awakened by the
abdominal pain.
As the medical staff tried unsuccessfully to empty the young woman's stomach
with a wide-bore tube, her condition rapidly deteriorated, and she had to be rushed to the
operating room. On opening her abdomen, it was seen that a section of the upper small
bowel appeared to have lost its blood supply. As the surgical team watched doubtless
horrified, the area of ischemia gradually extended until it involved most of the length of
the gut. Soon the small gas bubbles became visible in the intestinal wall. Their patient
died shortly afterward. Autopsy revealed massive clostridial overgrowth in the
esophagus, stomach, and the upper portion of the small intestine.
The unanswered question about Grace Lopat is not whether she was the victim of
enteritis necroticans, it seems almost certain she was. What is not known is the
underlying reason for the unchecked growth of clostridia in her intestine. The amount of
pork she had eaten before her earliest symptoms was not excessive; she was not
malnourished; she did not ingest any significant volume of food containing a trypsin
inhibitor. The only possible clue is her diabetes. The disease is well known to be capable
of causing a degree of immunodeficiency, which is one of the re:lsons diabetics are more
infection prone than the rest of us. But any indictment of a diabetic immunodeficiency is
weakcqed by the absence of previous or subsequent evidence that she is pariicularly
siixepijbk to akesses, ri-d-iiiio~~, oi &her mmife~tations of decreased resis;ance to
bacteria. In searching for some underlying cause, we were kft with the succinct
summarizing comment entered in Grace's chart by Ann Camp, one of the interns who
took good care of her in the MICU. She called her patient's disease "interesting and
mysterious."
Another of the few individual case reports of Pig Be1 involved a man in the
Netherlands who died 24 hours after being admitted with characteristic symptoms, in
1984. He had eaten an unspecified quantity of pork at a party the day before becoming
sick, but no other guests were affected. As the paper's authors write, "It is well known
that diabetic patients have a lower resistance to infections. It is therefore tempting to
speculate that this may have been a contributing factor." Neither the Dutch doctors nor
those of us who treated Grace can go any further than that.
Grace had improved sufficiently so that her breathing tube could be disconnected
from the respirator. Twenty four hour later, in her first fully alert moment since
admission, she opened her eyes. Within minutes she saw her mother looking down at her,
holding a large card printed with the alphabet, which Anne had made ready for just such
use. Grace gestured for the card, and pointing very slowly to each letter, she spelled out,
"I have a history exam on Friday." Eleven days had passed since the operation, and she
had lost every moment of them.
The improvement continued, although very slowly. It took almost three more
weeks in the MICU before Grace was ready to be transferred to an acdte-care floor. She
stayed there an additional two months and then moved to the hospital's rehabilitation unit.
She had lost a great deal of weight and considerable muscle mass in her legs, but she
knew that everything was recoverable with hard work. She was finally ready to discharge
from the hospital el 8 weeks after she had entered it.
It would be another four months before Grace regained enough strength to return
to college. Her mother considers her graduation two years later to have been the final step
in a triumph not only of perseverance and luck but of Bill's protecting spirit, too. A few
hours after Grace's reurn to wzkefuhess on thiit joyful morning four years ago, a
rainbow appeared in the sky, even though there had been no rain. Anne remembers
looking at it and being sure it was a good omen.
The "bip ideas" of the case bbPig-Bel":
The case "Pig-Bel" is mainly concentrated on the foltowing physiological
concepts:
1.
2.
3.
4.
5.
6.
Purposes of the blood. The crucial roles of white blood cells and body
immunity.
The interaction between blood glucose, diabetes and body immunity.
Homeostasis. The body fluids maintain homeostasis. Body temperature
regulation a phase of homeostasis. Causes of homeostasis disorders.
Electrolytes and their functions.
Regulation of respiration and oxygen therapy.
Digestion and absorption of digestive system. The functions of trypsin in
digestion, in body protection against parasites, and in body immunity.
Grow discussion's auestions:
1. Why the patient's abdomen was swollen and her body was bloated?
2. Could you find out the reasons for the blood stool and the paralyzed legs and
arms?
3. Could you clarify the functional interactions of white blood cells, diabetes,
trypsin, and body immunity?
4. There is any possibility of this disease occurring in Vietnam? How can we
prevent this disease?
Appendix D
Group Observations
Group I
Group members:
1. Ms. Tran Thi Cam Thuy iGroup Leader)
2. Ms, Tran Thi Kim Dung
3. Ms. Nguyen Ngoc Hue (Secretary)
4. Mr. Bui Tan I>oi
5. Mr. .Nisi Ngw Tmng
6. Ms. Tran Thi Kim Cuc
7. Mr.. Nguyen Van Thuy
8. Mr. Le Van Dai
Observations of group discussion
When the play stage started, all the members of the group moved immediately to
the first row of benches on the left side of the class. The students sat side by side, face-to-
face randomly with 4 students on one bench. They took about 3 minutes to get started,
preparing to answer the questions which I proposed and then one female student, who was
usually a little quiet in class discussion, raised her left hand suggesting the leader allow
her to express her ideas. The group began discussing the case.
Dung: "Based on the first question, I think that the patient's abdomen became larger
quickly just because the bacteria Clostridium concentrated on the intestine system causing
capillaries to break, and then bleeding happened. There also was a effect on nervous
system resulting in mental disorders."
Another female student immediately raised her hand, ready to join the discussion.
Hue: "I think the "Pig Bel" disease is caused by Clostridium perfringens. This is an
obligate anaerobic endospore-forming, gram-positive rod, strong gas producing bacteria.
This bacteria is very commonly found in soil, aquatic sediments and the intestinal system.
Because of its spores, food that has not been heated sufficiently could not kill
contaminating C. perfringens. In a favourable environment, especially in a rewarmed
meat dishes if large amount ingested, the endospores can germinate, and an enterotoxin
produced during sporulation in the gut, causes hypersecretion. Severe diarrhea comes
from this symptom. I think that C. perfringens produces neurotoxin so it causes disorder
in nervous system. The patient's very large abdomen is caused by gas produced."
Four students nodded meditatively, and then one of them start to talk. This time it
was a male student who had shared many good ideas during class discussion.
Doi: "I completely agree with Hue. The enterotoxin is a kind of neurotoxin that
depending on the amount could cause nervous disorder. Intestinal bleeding is mainly
caused by bacteria's production of gas; the intestine's capillaries were broken due to
being strongly expanded, the intestinal wall, I mean."
The female student who started the group discussion seemed to be impatient to
wait for the leader's permission, and began speaking immediately afterwards.
Dung: "About the patient's skin with great purple-gray blotches appearing every where,
I am guessing that the large amount of enterotoxin in blood resulted in difficult
circulation of blood; her skin k a m e bloiched."
The third female student of the group promptly added:
Thuy: "I think so. Her blood could not flow smoothly because of the bacteria toxin,
blood stayed still in skin capillaries and besides, intestinal bleeding was caused by the
same reasons when her abdomen was in muscle spasm."
It was the last female's turn to join the group discussion.
Cuc: (Her voice a little weak) "I am thinking that the patient's skin symptom probably
caused by skin gangrene. The bacteria's toxin was responsible for this. And I also
believe that the toxin blocked intestinal peristalsis and rhythmic contractions that
normally push along the intestine's contents. Water in intestine could not be absorbed
into blood and it came out from intestine's wall into her abdominal cavity."
The female student finished her speaking with relief, her voice becoming stronger
at the end of her statement. There was a short pause. One of the male students suggested
the group allow him and other males to smoke.
" OK. Go ahead" . A female responded. All members smiled. A male with loud voice
and north country accent, the second of the male students spoke out.
.Dai: "In my opinions, in order to bring all these symptoms about, the human body needs
a sufficient amount of bacteria, of their toxins. I am thinking that maybe the toxin caused
the blood to be infectious, appearing through skin's blotches. It is not easy at all to treat
diseases caused by endospored bacteria."
The whole group became noisy and discontented, I guessed. Some female
students whispered something and then a male student interrupted with his strong and
clear voice.
Doi: "I don't think so. The bacteria did not cause blood infection yet. Her skin
biotched just because of difficult circulation."
Dung: "It is impossible to treat infectious blood diseases."
A stronger conflict among these students appeared clearly. Dai's face became red,
his voice seemed to be excited.
Dai: "Not all infectious blood diseases are incurable. The infection of green-rod
bacteria, for example, causes infectious blood but there are very few incurable cases
reported."
The discussion changed the topic. Now the third male student who kept silent
started to participate.
Trung: "This kind of Clostridium lives naturally in a human's intestine. The
small amount of pork she ate the night before seemed not to be a cause of the terrible
"Pig-Bel"."
Dung: "Because of her diabetes, the patient had very weak immunity to
Clostridium."
Again all members nodded their heads. Suddenly, the last male student brought
the group back into the discussion.
Thuy: "This Clostridium caused gangrene. Gas production came from the environment
where they lived so it is not correct if we say blood circulation blocked. Due to lack of
oxygen, gangrene happened just within certain areas."
The group kcme excited. Dissent appeared.
Doi: ''1 don't think so. Air production came from the blood's oxygen."
Thuy: "Why had the patient almost no problems with respiration?."
There was no solution to this question. The group moved to another topic.
Dung: "The English model also had very weak immunity so she died immediately after a
few hours of eating contaminated food."
Doi: "It was caused by an excessive amount of the bacteria."
Thuy: "The model ate so many kinds of foods especially undercooked meat so the
bacteria produced excessively but she had no problems with mentally disordered
symptoms. In Grace's case things seemed different."
Hue: "The case study mentioned some tribes in New Guinea with a high annual mortality
rate. Their way of cooking helps the Clostridium perfringens multiply rapidly."
Trung: "The case study did not say that this disease happened in our country but in my
experience, through many years working at QN hospital, we have had many similar cases,
if not exactly the same. We call the disease enteritis necroticans. The clostridial toxin
causes the lack of oxygen in certain areas of the intestine. Cutting off the infectious parts
of intestine through emergency operation is the only method that we got to treat enteritis
necroticans."
Dung: 'Through this case study, we learned that in order to avoid this deadly disease
food, especially meat, must be cooked well, preventing clostridial multiplying in our
bdy.,'
Hue: "Roundworm Ascaris lumbricoides, which is usually found in our children, is a
parasite that secretes its own brand of trypsin inhibitor adding to what is already in the
poisoned food. So we have to protect our children from this parasite by feeding them
well-cooked and sanitwj food."
The group seemed confused about Hue's statement. Some opened the case to read
it again. The silence was interrupted by a male student.
S.Doi: "Yeah. I agree with Hue that trypsin secreted by the pancreatic gland is a
very important enzyme for hydrolyzing protein. In this case trypsin can fight against
Clostridium perfringens's toxin to destroy the invaders. Through this case study we could
learn many useful ways to understand the basic knowledge in the course and to make our
daily life safer."
The group was going to end the discussion by chatting some thing more about
their own experiences from workplace. Relaxed conversation lasted ten minutes more
and then the whole group went back to class for the "debrief' stage.
Group 2
Group Members:
1. Mr. Nguyen Quang Chieu
2. Mr. Le Quang Chanh (Group leader)
3. Mr. Nguyen Van Vinh
4. Ms. Hoang Thi Thanh Vy
5. Mr. Tran Van Tung
5. Mr. Cao Van Anh
6. Mr. Dang Thanh Xuan
7. Ms. Nguyen Thi Chung
8. Ms. Le Thi Lan (Secretary)
Observations of group discussion
Even though there were fewer female than male students (3 females, 5 males), the
discussion starter also was a female.
Chung: " We could relate the case study to our citizens' health and diseases.
Through more than 8 years working at LD hospital as a clinical technician I think that the
"Pig-Bel" disease is widespread in Vietnam. We are often confronted with the slightly
different symptoms, however, patients' bodies are not bloated and swollen as Grace's
was. It usually happens with people living in the countryside eating undercooked food,
with malnourished children attacked by parasites. In almost all cases we found a lot of
parasites and Clostridium. This is an obligate anaerobic bacterium which is spore
forming. In our country, it is expensive to culture this bacteria in anaerobic condition so
it is not easy to determine their species. Incubation period is about from 24 to 48 hours.
Enterotoxin causes diarrhea and vomiting. An intestine infected Clostridium would be
swollen with blood. Stools are sometimes bloody. Its toxin causes intestinal paralysis; no
contractions results in necrosis. In hospitals, patients with enteritis necroticans often have
to undergo operations to cut out the inflammation intestine after the whole intestinal
system has been washed completely. Antibiotics must be taken."
The group kept silent for a while. Maybe they were thinking the ideas presented
by Chung.
Chieu (a student who always had many good contribution to discussions in class): "I
propose that we should focus on the big ideas of the case from the 3 sections we have just
studied: blood, cardiorespiratory system, and ingestive system."
Anh: "I'm wondering whether enteritis necroticans could be the "Pig-Bel" or not.
Symptoms of the two diseases are very similar to each other. In my own opinions, the
"Pig-Bel" is enteritis necroticans."
One decision-making process appeared strongiy. Some other students showed
their agreement by nodding their heads. The leader s f the class at that time was a member
of the group, and he started to talk.
Tung: "I fully agree with Chung about this case. In Vietnam, however, we could hardly
find other symptoms like skin blotches, and mental disorder."
Chanh (His peers call him Robert Chanh because of his sideburns and thick beard so they
usually laugh a lot whenever he speak out. This discussion is an exception; the group
kept silent when he started): "I think that the case study could cover the three sections of
the physiology course we just finished in its pathology. Usually there are about 6000 -
8000 / mm3 white cells but in this case white cell count to 280001 mm" This means that
there were foreign invaders in the patient's body. This bacteria could produce two kinds
of toxin. One an exotoxin, the other an enterotoxin. Enterotoxin is a neurotoxin that
blocks acetylcholine release at neuromuscular junctions by binding to the synapses of
motor neurons and preventing the release of the neurotransmitter acetylcholine. As a
consequence, muscles do not contract in response to motor neuron activity, and flaccid
paralysis results. This activity of the enterotoxin could be considered to explain why
Grace, the patient can not walk and or feel her hands and her legs within nearly 48 hours
after eating the Chinese food. (pause for a while) Besides, the bacteria's enterotoxin
produces a large amount of gas, mainly CO, , blocking blood circulation in the intestine
because CO, enlarges the vein system. With diffusion and absorption functions through
intestine wall blocked, fluid went out to her abdomen cavity. Gangrene set in.
Enterotoxin also causes skin capillaries to disfunction; blood vessels could not contract so
the patient's skin became blotched."
Some students seemed to be deep in thought, while others discussed Chanh's
ideas.
Vinh: (His voice very strong and full of confidence ) "I do not agree with Chanh's ideas.
I think this Clostridium has no exotoxin. All the symptoms could be caused by
enterotoxin. CO, causes the intestine to expand resulting in low blood pressure, weak
pulses and finally fatality."
The group discussion's atmosphere became more seriously discontented. Chanh
probably felt a little hurt, he tried to defend his ideas.
Chanh: T O , make blood vessels expand for sure. Clostridium could release enterotoxin
and cxotoxin for sure. Exotoxin is often a special proiein."
Tung: "Yeah. 0.2 ml of clostridial toxin could kill an adult."
Chieu: "I agree with Chanh about clostridial toxins. This bacteria has both enterotoxin
and exotoxin and because of positive gram bacteria, toxins could be released directly to
the environment around. I also wonder whether or not the "Pig-Bel" is our common
enteritis necroticans but to my knowledge, only Clostridium pesringens can cause
gangrene."
Chanh: "I am sure that only an exotoxin could cause mental disorder, I mean neuron
functional disorder. The patient could not control herself from screaming, and
complaining loudly."
Chung: "I am thinking about the production of a vaccine that could prevent this disease.
What do you guys think?"
Chanh: "I do not think that we have to produce a special vaccine for this disease because
we can control it easily by eating only cooked meat."
Anh: "Live clostridiurn secrete exotoxin, and dead clostridium corpses disintegrate and
release enterotoxin."
Tung: "Yeah. And because of an excessive release of CO, , blood vessels expanded
resulting in a swollen body."
Vi: (a female student who often spoke in class discussion, but who was rather quiet in
case study's "play" stage) "I believe that with her chronic diabetes, the patient had very
weak immunity to fight against the bacteria so she got terribly ill."
Chieu: "We did talk about how clostridial toxin causes mental disorder, the patient's
distended intestine and her bloated abdomen too. These symptoms caused excessive fluid
retention, mineral absorption failure and then kidney failure. The amount of ure, and
potassium in her body resulted in disordered acid-base balance. This was also a reason
for her bloated body, rapidly increasing from 125 to 185 pounds."
tan: (who, as a secretary, rarely spoke) "One of my own children experienced the similar
symptom when she was in daycare. I do not know what she ate over there but we had to
send her to hospital immediately. Fortunately she did not undergo any operation, just
antibiotic drugs and serum support. So I think we have to be careful with uncooked
Vi: "I agree with Lan."
The group became noisy talking about Lan's child. They asked many things about
the child. Dixussioc seemed to be ended. Students were going to pstiicipate in the
"debrief" stage of the case study. I heard them assigning a group representative for the
next stage,
Group 3
Group members:
f . Mr. Tran Duc Tho (Secretary)
2. Ms. Phung Thi Tho
3. Ms. Dang Thi Thu Huong
4. Mr. Le Thien Phong
5. Ms. Tran Thi Ngoc Huong (Group leader)
6. Mr. Dao Huong
7. Ms. Dinh Thi Thuy Thanh
8. Mr. Tran Van Hung
Observations of group discussion
Three male students did not attend class so only 8 group members showed up.
Fortunately the number of males and females was equal in group discussion.
Again a female student began to discuss fust.
Thanh: 'The case study has connections to the three sections of the physiology course we
just finished. I found that the mechanism of diabetes has a very negative effect on the
human body's immunity to fight against foreign invaders such as viruses, bacteria. The
patient, who was very young, with her chronic diabetes got completely ill even af,cr
eating a small amount of pork. The case study indicates Clostridium and we have many
species of Clostridium. What species causes the "Pig-Bel"? Do you have any ideas about
this?"
D, Huong: "Cbstridiai roxh causes gangrene. The mechanism of gangrene is to cause a
k k of cxygen, mtz;,e~t~, F-S, water which come frcm bl& fix tissues'
consumption. Once gangrene has appeared, bleeding will be a consequence. In this case
the bacteria p r o d m gas, probably CO, which causes veins to expand, blood pressure to
decrease, and then respiration to fail. We know about enteritis necroticans in our country
but we are not sure whether the "Pig-Bel" is enteritis necroticans or not."
N Huong: "The patient's intestine was paralyzed because of acetylcholin blocking caused
by clostridial toxin."
T. Huong: "Yeah. Diabetes makes our body become too weak to resist harmful bacteria.
That's why the number of white blood cells increased so much: 28 thousand in this case.
Clostridium toxin binds to the synapses of motor neurons and prevents the release of the
neurotransmitter acetylcholin."
Phong: "Because of enteritis necroticans, water and food could not go through the dead
intestine. The blockage caused nausea, and vomiting and the liquid went naturally from
intestine to abdominal cavity based on the mechanism of diffusion. The patient's girth
became larger not only because of intestinal gas but also because of the liquid in her
abdominal cavity."
Tho: "Yeah. And I want to add one more thing: the patient's body became bloated which
is also accounted for by her kidney failure; with her chronic diabetes, her kidneys were
not strong enough to absorb and to secrete waste substances. The acid-base balance was
disordered. Acid seemed to be accumulating at a too high level in her blood which finally
brought her to coma."
Hung: "I agree with you all, and we have one more important piece of information about
the patient. Do you find it strange that her original weight was 125 pounds and just
before the operation she gained 60 pounds (185 pounds) ? If this is true, I think that the
gs p-&fft;oa ws vei'J, s~ bxt c.- .,r gi*, kr whok Wj blew op, bloated on acc~unt
of the Mockage of liquid intake through mouth and veins."
A female student opened her book, which was written in Vietnamese. She read
for a while and nodded her head as if she found something interesting related to the case
study. Others seemed to wait for her ideas collected from the book. And then she joined
the discussion.
Thanh: (Hmrn) "Listen to me, people. I just found something here. We can come to a
conclusion about whether the "Pig-Bel" is enteritis necroticans. They say (read the book)
about "Air producing enteritis necroticans": Caused by Clostridium." (She looked at her
peers to see whether they were paying attention to her reading or not). "The dead tissues
caused by protein destruction. The body bloated and gas produced. Toxic infection
quickly prevails tfrroughmt the whole body. High temperature, s t pulse, vomiting,
exhaustion, partial paralysis, and sometimes spasms occur. The color of the skin
changes, sometimes appearing burnt, sometimes appeared bruised."
She stopped reading the book, waiting for others' response.
Tho: 'There was one thing different, the patient did not have a high temperature."
Thanh: 'That is not important, sometimes it depends on individual."
D. Huong: "I think that the "Pig-Bey is enteritis necroticans. But I wonder why the case
study did not mention Vietnam in the list of the counhies where the "Pig-Bel" exists."
Tho: "Usually we have more simpler cases than that of the American patient. If a person
does not get seriously ill, a course of medicine is enough. If the case is more severe,
intravenous fluid must be supplied quickly."
Phong: "We have leanred many things from the case study. In order to prevent this "Pig
Bef" we must cook f d well and under sanitary conditions."
N. Huong: "Vietnamese people like raw and fresh bloody dishes very much. I think we
have to educate people about titis disease and recommend that they nor to eat sucn dishes
any more."
Hung: "Quite a few of Vietnamese people get diabetes. Diabetic patients, however,
should follow their doctors' instructions about food."
D. Huong: "We also should avoid of eating food at feasts or banquets. The more the
variety of the cuisine is, the easier it is for them to acquire bacteria infection."
Thanh: "Yeah. I agree with you. And our government should be concerned with public
sanitary sources; clean water supply, good sewage system processing, good garbage
disposal, etc."
N. Huong: "And the government should also pay attention to food processing. Food
must be clean."
Phong: 'The most important thing is for families have to take care of themselves,
especially their children."
Group 4
Group members
1. Ms. Nguyen Thi Kim Phuong
2. Ms. Do Thi Le
3. =. He V m M m
4. Mr. Tran Ngoc Nhon
5. Mr. Van Thien Mnh (group leader)
6. Ms. Nguyen Thi Nga (secretary)
7.M. L e # i m M g a n
8. Ms. Nguyen 'T'hi Bach Ngoc
Observations of group discussion
Phuong: "This is an interesting case raising many issues related to the course. First of
all, the mechanism of homeostasis helps our bodies regulate and maintain the constancy
of the internal environment at appropriate levels so that glucose blood, CO, and pH levels
remain balanced. Kidneys, lungs, heart, sweat glands, salivary glands, skin, central
nervous system, and endocrine glands are responsible for the homeostatic processes. The
patient had chronic diabetes so the high blood glucose level brought her trouble. Let's
consider her bloated body."
Nhon: "I think that the Clostridium produced air and toxin which made the patient's
intestine bloated."
Ngan: "Yeah. And Clostridia in a high numbers would dominate other microcrobes,
increasing their population quickly, and releasing their toxin. This toxin is a kind of
neurotoxin which binds to synapses of motor neurons and prevents the release of
Acetylcholin, a kind of neurotransmitter that increases the intes tind contraction. Gas and
other materids exchanged more slowly and finally the gut lacks of oxygen resulting in
gangrene.''
Nhon: "I also think that the fluid exchange, I mean water, minerals, and electrolytes was
blocked by that necmsis. The blockage of bocty fluids caused her body to become
swolfen."
Ngm: 'CIoc~idia in w d m e sumkrs zrr ~ T A inhabitats of the gut, md ii&
harmful. Usually they live in harmony with other bowel organisms and with the various
physiolog.icd substances wirh which they come into contact forming a cornunity of
organisms in our gut. One thing we are sure that the patient's intestinal homeostasis was
upset because a massive overgrowth of clostridia occurred. The clinical symptoms arc
very similar to enteritis necroticans frequent in \ ietnam; blown-up abdomen, vomiting,
bloody stools including with black feces, respiratory failure, weak vessel pulsing but no
body bloating. I am wondering whether it is the "Pig-Bel" or not."
Le: "Clostridia germinated rapidly, with their toxin release blocking the neurotransmitter
acetylcholin so her intestine became inactive. Fluid went through from intestinal wall to
abdominal cavity and made her abdomen swollen. I think this patient had diabetes so the
symptoms were a little different from our enteritis necroticans, This "Pig-Bel" might be
enteritis necroticans."
Phuong: "Yeah. I think the author of this story did not come to Vietnam" (all laughing).
"Actually in our country children get the disease more often than adults."
Ngoc: "Yes. Because children have weak immune system to attack the invasion of the
bacteria. Besides, our children's guts in general are the habitat of parasites. Roundworm
Ascaris lumbricoides release a special chemical that can be trypsin inhibitor. Trypsin is
an enzyme that could destroy clostridia. And one more important thing is sweet potatoes
in our country are still a main source of starch for meals for many families in the
countryside which are too poor to get rice. So that's why our children often get this
disease more than adults."
Nhon: "I completely agree with you."
Ngoc: "Fortunately Vietnamese people still rarely have diabetes. But the organization of
ow public sanitary systems is quite poor; food, water, and sewage are still a big concern
so we have been plagued by this disease."
Nam: "Yes. I have one thing to add to our discussion. Hmm.. When our brain Jacks of
oxygen, we go into a coma." fal l laughing).
Phuong: "We still have many things to talk about regarding this case. I am hoping that
we will have more cases to discuss. This is a way to get more understanding of the
course."
Many said yes. Students got up and left the room to go back their class next door.
Appendix E
Background Survey vith Consent Form
(Student's background with consent farm written in Vietnamese)
Appendix F
Course Evaluation
(Student's course evaluation wriiten in Vietnamese)
Appendix G
Self-Evaluation
(Student's self-evaluation written in Vietnamese)
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rif c8c kign nny 4. KhiEm t6n \-2 khfo 160 phHn tich quan di8m clja cfic han dE v5.n
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thHo lu3n
Appendix H
Midterm Examination Questions
1 . What is the main function of erythrocytes? leukocytes? platelets? Where does it
originate?
2. What are the advantages of blood banks? Are there any disadvantages? If so, what
are they, and is there a way of counteraction these disadvantages.
3. Describe the basic steps in the clotting process, and try to relate the facts to one of
hemorrhage diseases if you know.
4. Trace a drop of blood through the shortest possible route from the capillaries of the
foot to capillaries of the head.
5. What are some examples of disorders that cause hypertension of a persistent kind? Of
what importance is diastolic blood pressure?
6. Describe normal breathing, including 2 phases, respiratory rates, mechanism of
breathing and nerve control.
7, What are some possible causes of lung cancer?
8. Trace the path of an indigestible object from the mouth through all parts of the
alimentary canal to the outside and tell what happens on the way.
9. Name and describe the functions of the enzymes in the stomach juice. How do they
function in the small intestine?
10. Describe what happens in the formation of a peptic ulcer. Where does it occur?
