Constructivist, Problem-Based Learning Does Work: A Meta-Analysis of Curricular Comparisons Involving a Single Medical School

Abstract

Effects of problem-based learning as reported in curricular comparison studies have been shown to be inconsistent over different medical schools. Therefore, we decided to summarize effects of a single well-established problem-based curriculum rather than to add up sometimes-conflicting findings from different problem-based curricula. Effect sizes were computed for 270 comparisons. The results suggest that students and graduates from the particular curriculum perform much better in the area of interpersonal skills, and with regard to practical medical skills. In addition, they consistently rate the quality of the curriculum as higher. Moreover, fewer students drop out, and those surviving need less time to graduate. Differences with respect to medical knowledge and diagnostic reasoning were on average positive but small. These outcomes are at variance with expectations voiced in recent contributions to the literature. They demonstrate that constructivist curricula can have positive effects on learning even if they deemphasize direct instruction.

Notes

¹This may not be the only source of the effect. Problem-based schools also tend to initiate students in the secrets of patient–doctor communication at an early phase and allow them to apply these skills on simulated patients.

²One may ask whether emphasis on the acquisition of skills is an idiosyncratic attribute of the particular school studied rather than an intrinsic element of PBL. The answer is that almost all problem-based schools introduce professional skills at an early stage in the curriculum. This is because developers and theoreticians in the PBL domain share the belief that what cognitively belongs together should be taught together; practices should be embedded in appropriate theory. Therefore, until recently, one would find early skills training almost exclusively in problem-based schools, whereas conventional schools tended to postpone this kind of training to the clinical rotations in the latter part of medical education. This may be the reason that problem-based schools, not only the school under study, are doing better than conventional schools in this respect, as also noted by a recent review (Koh, Khoo, Wong, & Koh, 2008).

^a Effect size is expressed as Cohen's d. Bold indicates an average d, weighted over classes of students and numbers of students.

^b For a description of the Progress Test, see text.

^c Samples were selected at random from pools of volunteers.

^d The shorter the processing speed, the better.

^e Belgian medicals schools have a 7-year curriculum, so the Ghent and Antwerpen schools contributed 4th- to 7th-year students.

^f The shorter the study duration, the better.