Long-term follow up of factual knowledge after a single, randomised problem-based learning course

BACKGROUND The long-term effect of problem-based learning (PBL) on factual knowledge is poorly investigated. We took advantage of a previous randomised comparison between PBL and traditional teaching in a 3rd year course to follow up factual knowledge of the students during their 4th and 5th year of medical school training. METHODS 3rd year medical students were initially randomized to participate in a problem-based (PBL, n = 55), or a lecture-based (LBL, n = 57) course in basic pharmacology. Summative exam results were monitored 18 months later (after finishing a lecture-based course in clinical pharmacology). Additional results of an unscheduled, formative exam were obtained 27 months after completion of the first course. RESULTS Of the initial sample of 112 students, 90 participated in the second course and exam (n = 45, 45). 32 (n = 17 PBL, n = 15 LBL) could be exposed to the third, formative exam. Mean scores (+/- SD) were 22.4 +/- 6.0, 27.4 +/- 4.9 and 20.1 +/- 5.0 (PBL), or 22.2 +/- 6.0, 28.4 +/- 5.1 and 19.0 +/- 4.7 (LBL) in the first, second and third test, respectively (maximum score: 40). No significant differences were found between the two groups. CONCLUSION A small-scale exposure to PBL, applied under randomized conditions but in the context of a traditional curriculum, does not sizeably change long-term presence of factual knowledge within the same discipline.