the effect of problem-based learning on education and recall of medical students in a course of basic immunology in comparison with lecture –based learning

background: according to the available evidence and experiments, problem-based learning is one of the most successful methods to achieve higher educational objectives. in this method, the discussion about the medical sybjects to be learned by the students is based on a real clinical case and participation of the students. various advantages and disadvantages of this method have been addressed in different studies. purpose: in order to evaluate the effect of this method in our educational framework, we compare two educational methods, problem-based learning and lecture-based learning, in terms of students' education and recall. methods: it is an experimental study. two topics of basic immunology were chosen after holding discussion meetings. the students were divided randomly into two groups. each topic was taught to the two groups of students using both methods alternately. students' educational achievement was evaluated with pre-test and post-test exams. four weeks after these sessions, short-assay exams were used to evaluate the students' recall. results: the difference of pre-test results between the two groups was not statistically significant, whereas the difference of post-test scores was statistically significant. there was no statistically significant difference in the students' recall between the two groups. conclusion: considering the exchange of two methods between the two groups, the effect of personal differences was eliminated in this study, and since there is no significant difference in the pretest scores, the difference of posttest results could be related to the effect of pbl. according to the results of this study and with conducting additional experiments, the problem-based learning could be adjusted with the specific educational framework in our country.