Use of NBME examinations to assess retention of basic science knowledge.

About 10 years ago results of the National Board of Medical Examiners (NBME) "Minitest," comprised of samples of questions from NBME Part I and Part II tests, indicated that the change in performance in the total basic science examinations would be minimal between the second and fourth years of medical school. By inserting samples of Part I basic science questions into Part II, large scale tests could be made of the change in performance. In two pilot projects, in a longitudinal study of the same students at a two-year interval, in a cross-sectional study of two groups of students at the same time, and in a comparison of performance of basic science questions in the Federation Licensing Examination (FLEX), the prediction of the minitest results was sustained. Overall performance on all basic science questions decreased only a little. However, the changes in the individual disciplines ranged from a consistent improvement in pathology to a substantial decrease in biochemistry. Pharmacology and behavioral sciences fluctuated between small increases and decreases. Physiology, microbiology, and anatomy decreased consistently, but not as much as biochemistry.