The aim of this study was to compare the educational effects of previously developed case-report scenarios and newly developed narrative scenarios used in problem-based learning (PBL) at the Yamaguchi University School of Medicine. 1) Students' reports submitted after they had completed PBL sessions were reevaluated, and the educational effects were compared statistically between the 2 scenario types. 2) To reevaluate the students' reports, the learning effects expected of PBL classes, reported by university medical schools in North America, were used. 3) The PBL using narrative scenarios was found to be more effective, particularly for the acquisition of clinical reasoning ability and comprehensive patient treatment. 4) Our results show that the scenario is an important factor in PBL.