The participants were first year medical undergraduate (UG) students admitted from 2007-2010 in Kasturba Medical College Manipal, Manipal University, India. A total of 773 students participated in a systematically conducted PBL session in physiology during the middle of their academic year after having experienced at least 4 months of traditional teaching in physiology.

The students were initially briefed about the principles, methodology, and practice of a proper PBL session. They were then divided into groups of 10 and a tutor/facilitator from the faculty was assigned to each group. Thereafter, PBL was conducted in 2 sessions. The first session was for one hour, wherein the students introduced themselves and elected a leader and a scribe. Then they were given the first part of a clinical case comprising history, symptoms, and signs. They went through the case details slowly and thoroughly, ensured they understood the meaning of difficult and novel terms and after detailed discussion, identified their learning needs and distributed the work to be done among themselves. They were free to meet amongst themselves later for further discussion. The second session, held one week later, lasted for 2 hours. In the first hour, the students shared their knowledge and understanding, asked for further information related to the case, and discussed the problem again at length until they reached a consensus. In the second hour they presented their cases to the other groups, stressing mainly the methodology the group used, the way they approached the problem, the questions they generated, and finally their understanding of the pathophysiological aspects of the case and the learning outcomes they achieved. After each presentation, the members of other groups were free to ask questions or to add relevant comments.

At the end of the session, the objective of this research study was explained to the students and they were invited to participate. Informed verbal consent was obtained from all those who volunteered. They were asked to fill in a 15-item questionnaire evaluating their preferences for PBL or traditional pedagogy as they had experienced it in the physiology class. The questionnaire was adapted and modified from those in existing literature (Appendix 1). An open-ended qualitative section captured qualitative quotes from the respondents, which were thematically analyzed. In addition, students were asked to mention where they had experienced at least 10 years of their schooling before entering medical school: India or abroad.

Responses to the items in the questionnaire were scored as follows: traditional much better (1), traditional better (2), both the same (3) PBL better (4), or PBL much better (5). Univariate analysis was performed and the scores were compared using the one-sample t-test and Wilcoxon signed rank tests. Results across groups (at least 10 years of schooling in India vs abroad; category “I” vs. “A”) were compared using the twosample t-test. After considering the results of the first analysis, it was felt worthwhile to further study the data in detail. Since no significant differences between the “I” and the “A” groups were found (data not shown), the data was pooled for further analysis. Responses were recoded as traditional much better (2), traditional better (1), both the same (0), PBL better (1) and PBL much better (2). For each item of the questionnaire, the mean values for the responses in the traditional groups (1 and 2) were compared with the mean values for the responses in the PBL groups (1 and 2) using the unpaired two-sample ttest. The difference between the means was calculated and significance was determined.

Out of the 800 students recruited for the study, 773 returned a completed questionnaire. Of these, 159 students were from category “A”, whereas 614 students were from “I”. For most of the items, the students rated PBL to be better than the traditional method. PBL scored highest for instilling the capacity for teamwork, preparing students to face clinical postings, development of reasoning, independent thinking, curiosity, and a questioning attitude, and finally, for generating good interpersonal relationships amongst students. Irrespective of their schooling, the majority of the students believed that the overall value of PBL was greater than that of the traditional method of teaching (Fig. 1). Table 1 shows the results of data pooled from both the ‘I’ and the ‘A’ groups (scoring pattern 0, 1, 2). There was a highly significant difference between the mean scores for PBL and traditional methods for most of the items of the questionnaire except for “learning efficiency”, “understanding principles”, and “student-teacher relationships”. Though not significant, scores for learning efficiency were higher for PBL. As far as understanding of principles was concerned, the majority of the students were of the opinion that the traditional method was better (44.02% of the “I” group and 46.09% of the “A” group), while the rest were more or less equally divided between “both the same” and “PBL better”, corresponding with the mean score in favor of the traditional method (Fig. 2). Moreover, even with detailed analysis of the pooled data, the mean scores for the traditional method were higher (Table 1), suggesting a tendency for a slight preference towards the traditional method (P=0.051). In case of student-teacher relationships, the majority of students from the “A” group believed that it was similar for both the modes of teaching, though amongst students of the “I” group, approximately a third believed PBL was better, another third felt that both had equal value, and the remaining third opined that the traditional mode was better (Fig. 3). Pooled data analysis found marginally higher mean scores for the traditional method, but these were not statistically significant.

Comments from students captured interesting observations ranging from questioning the “expertise” of teachers in using PBL methods, the environment, and the size of the group, to a sense of ownership and better self-esteem gained after the experience of PBL. They were classified into various themes.

Teamwork: Some students complained that all group members did not participate equally, and they felt that this hindered their learning process.

Assessment: Some students commented that the participation and the performance of the group members during the PBL process should be formally assessed and this assessment should play a vital role in the final exam/evaluation/grading.

Value for time: Some students thought PBL was a waste of time as it did not help them to prepare for the exams. Others commented that it would help them to become better clinicians.

Role of tutors: Some students felt pressured and unable to think with an open mind as they thought the tutor was too strict. Some specific comments were as follows: first, there is no need for tutors in a PBL class; second, our tutors were too strict. It hampered my learning; third, tutors need more training to conduct PBLs.

The majority of our students perceived that as far as acquisition of knowledge and information gathering in physiology was concerned, PBL was better than traditional teaching (Table 1). Present study addressed only student perceptions and did not directly test the level of acquired knowledge. Students also felt that the traditional method was superior to PBL for understanding general principles and concepts (Fig. 2). Problem- based learning students were also found to have the same perceived level of anatomy knowledge as the students of more traditional educational approaches in eight medical schools in the Netherlands [5]. PBL has been documented to have an adverse effect on some students who have to adopt a shift in their mindset, as they now need to explore rather than merely receive content knowledge [6]. Based on this, there could have been differences between the “A’’ and “I” groups, as, unlike students in group “A”, the “I” students had probably never been exposed to a PBL approach, and we expected to find a preference for PBL in the “A” group students. However, contrary to our expectations, we found no significant differences between the groups. It appears that the preference for traditional learning is not shaped by prior exposure to PBL and is not merely due to the apprehension associated with a need for a shift in mindset. The drawback of PBL is the purported stress that students feel about the perceived danger of PBL leading to gaps in understanding of general principles and concepts, further complicated by such incorrect understanding not being rejected but being corroborated by other naive students and untrained/inexperienced tutors [6]. This would tilt the balance in favor of traditional teaching wherein the experienced faculty teachers are traditionally expected to ensure that all the necessary and important principles and concepts have been taught.

The amount of basic science knowledge that is sufficient to equip an undergraduate to successfully and confidently function as a medical practitioner is difficult to determine. Moreover, studies indicate that PBL does not impact knowledge acquisition, but impacts application of knowledge [7]. As far as learning efficiency was concerned, there was no significant difference between preference of students for PBL vs. preference for the traditional method (Table 1). Our results support a recent review which reported no unequivocal evidence in favor of PBL enhancing learning [7]. Our study was based on students’ perceptions; though their knowledge and understanding was not assessed by any evaluative process, the fact that they self-evaluated their knowledge and its application as a part of their learning objectives is valuable in itself.

PBL students consistently find their course more enjoyable and demonstrate better interpersonal skills compared with traditionally trained students [8]. Making learning fun and enjoyable is an essential method of driving individual and group learning [9]. We obtained encouraging results as students felt that PBL provided more personal enjoyment and satisfaction than the traditional method of teaching. PBL also scored higher for motivation and stimulating interest.

Through their interactions, students learn skills that are highly relevant to their future work as doctors, such as teamwork, leadership, and delegation [10]. Ultimately, graduates of PBL curricula demonstrate equivalent or superior professional competencies compared with graduates of more traditional curricula [10]. PBL was rated better for enhancing interpersonal relationships and for instilling the capacity for teamwork (Table 1) implying that students perceived these benefits of PBL.

PBL requires tutors to function as facilitators rather than acting as providers of information. More than the tutors’ subject- matter expertise and their ability to explain concepts in a way that is easily understood by students, the ability of tutors to communicate informally with students has a greater impact on learning at each of the PBL phases. This informal communication also creates a less threatening learning environment promoting a free exchange of ideas [11]. We found no significant differences in the number of students who preferred the traditional method versus PBL (Table 1, Fig. 3). However, as mentioned in the results, students wrote some interesting comments regarding the role of the tutor. Tutor expertise has a significant effect on student learning outcomes [12]. In a PBL setting, the boundaries between the facilitator and student are noticeably reduced, providing opportunities for the student to be empowered in raising pertinent questions challenging existing issues in relation to a PBL problem [13]. New attitudes and skills may be required of the teaching faculty so that they are willing and competent to deal with the PBL method. It is debatable whether the perceptions of our students were affected by the subject expertise of the tutors or their training, but hints from answers to the open-ended questions about serious concerns regarding the role played by some tutors indicate the need for tutors to understand the philosophy and methodology of PBL so that they can manage the learning process better.

The hallmark of any PBL approach is to generate questions in an effort to systematically analyze and solve the problem, and, not unexpectedly, the PBL method of teaching has been shown to be an effective instructional tool to foster critical thinking and problem solving skills among medical students [10]. Our study adds importance to such knowledge, as the students themselves perceived and rated PBL higher than traditional teaching for development of reasoning, curiosity and a questioning attitude, and independent thinking, all the characteristics needed for successful and efficient patient care and for lifelong, independent, self-directed learning.