Effects of conventional and problem-based medical curricula on problem solving.

This study examined the reasoning processes of beginning, intermediate, and senior students in two medical schools with different curricular formats. One school had a conventional curriculum (CC) where basic science was taught one and a half years before the clinical training, and the other had a problem-based learning curriculum (PBLC) where basic science was taught in the context of clinical problems and general problem-solving heuristics were specifically taught. The students were asked to give diagnostic explanations of a clinical case, both before and after being exposed to relevant basic science information. Two distinct modes of reasoning were identified, each reflecting a curriculum type. A predominantly "backward-directed" hypothetico-deductive mode of reasoning was found in the explanations of the PBLC students, and a "more forward-directed" pattern of reasoning was found in the explanations of the CC students. Students in the PBLC produced extensive elaborations using relevant biomedical information, which was relatively absent from the CC students' explanations. However, these elaborations were accompanied by a tendency to generate errors. These results have important implications regarding the strengths and weaknesses of the two types of curricula.