Performance and preference of problem-based learning (PBL) and lecture-based classes among medical students of Nepal

Introduction

Sir William Osler, referred to as the father of modern medicine, emphasized the role of teachers in helping students to observe and reason. He recommended for teachers to abolish the traditional lecture method of instruction.¹ PBL (problem-based learning) is a newer active learning educational strategy that has been extensively tested and used in recent years.² PBL is an integral part of teaching in the undergraduate medical education of several medical schools around the globe, including Patan Academy of Health Sciences (PAHS), a government medical school of a non-Western LIC (low-income country), Nepal.² The PBL process was pioneered by Barrows and Tamblyn at the medical school of McMaster University in Canada in the 1960s.³ Students like PBL because it is student-focused, allows active learning, and leads to better understanding and retention of knowledge.^4,5

Students take more interest and responsibility for learning, look for resources like research articles, journals, internet, textbooks, etc. and themselves resolve the contextual problems given in PBL.⁶ PBL enhances content knowledge and simultaneously fosters the development of communication, collaboration, problem-solving, critical thinking, and self-directed learning.^7,8 PBL emphasizes lifelong learning by developing the potential to determine goals, locate appropriate resources, and assume responsibility for what one needs to know.⁹ It helps students for long-term knowledge retention and improves competency as physicians after graduation.^10,11 PBL has gradually been adopted by several medical schools around the globe for undergraduate education.^12–14

PBL encourages students to ask questions, search references, and think of logical answers. On the other hand, PBL is resource-intensive and requires more physical space, computer resources, and more staff to facilitate PBL sessions.¹⁵ Students also report uncertainty, information overload, and inability to determine the required depth and relevance of information available.¹⁵ This study aims to compare students’ understanding and knowledge retention of topics taught through PBL and lectures, and also compare students’ perception of PBL and traditional lectures, among the first two batches of medical students of PAHS who passed in 2016 and 2017.

Methods

Results

Discussion

This study showed that students mostly liked being taught by both PBL and lectures. PBL was preferred for physiology, pathology, and pharmacology-related concepts, lectures were preferred for biochemistry and microbiology-related topics, and a combination of both for anatomy. Overall, the respondents wanted to be taught the same concepts via both PBL and lectures for anatomy. A meta-analysis by Nandi et al. compared the newer PBL curriculum and the conventional lecture-based mode of teaching undergraduate medical students. They concluded that a combination of both the conventional lecture-based and newer PBL curricula would provide the most effective training for undergraduate medical students.¹⁷ However, their findings were not subject-specific.

This study showed understanding and knowledge retention of students remained the same for topics taught by PBL compared to topics taught by lecture. There was no statistical difference in the median score obtained for PBL and lectures for the understanding and knowledge retention questionnaire (17 and 16, respectively). However, most other studies show better understanding and knowledge retention with PBL than lectures. A study by Albanese et al. showed that the PBL students score higher than the students in traditional courses. They also concluded that the reason for higher scores in PBL are the learning competencies, problem-solving, self-assessment techniques, data gathering, behavioral science, etc. of PBL students.¹⁸ Similarly, a study from Pakistan showed the mean score in the group exposed to PBL was 3.2 ± 0.8 while those attending lecture based classes was 2.7 ± 0.8 (p = 0.0001).¹⁹ Another study on students of mathematics from Slovenia found that students exposed to PBL were better at solving more difficult problems.²⁰

This study involved students taught through PBL in the first and second year of medical school i.e. basic science years and showed equivalent results compared to lectures. However, another study on PAHS students showed that PBL imparts long-term knowledge retention through students’ active participation.²¹ Wun et al. have also found that PBL which is started in the initial years of medical school is associated with more active participation, interaction, and collaboration among students, and PBL students score higher too.²² Another study on nursing students found that all students with higher or lower grades showed a significant increase in scores among students in the PBL group, but only students with higher grades showed a notable increase in scores among students in the lecture group. Learning motivation was also found to be significantly higher in the PBL group (t = 2.608, p = 0.012).²³

A few of the respondents qualitatively reported in this study that some students in the PBL group worked harder than other members of the same group to prepare and participate in discussions. They also found the time allocated for each topic was not sufficient at times. Silva et al. reported that teamwork and the time involved are factors which can limit PBL learning.²⁴ According to Wood, major disadvantages to this process involve the tutor facilitation and utilization of excessive resources.¹⁵

Conclusion

The understanding and knowledge retention of students is the same for topics taught by PBL compared to topics taught by conventional didactic lecture. PBL is preferred for physiology, pathology, and pharmacology-related concepts, whereas conventional didactic lectures were preferred for biochemistry and microbiology-related topics, and a combination of lecture and PBL sessions were preferred for anatomy during the basic science years of undergraduate medical education. Students prefer community-based programs and lecture sessions delivered by a group of faculty members for CHS. In contrast, they prefer a bedside teaching and hospital ward-based teaching methodology for ICM rather than lectures and PBL.

Data availability