Using a standardized-patient examination to establish the predictive validity of the MCAT and undergraduate GPA as admissions criteria

Abstract

Performance of senior medical students on an objectively scored examination of clinical competence based on standardized-patient cases was used to assess the predictive validity of the two most commonly used admission measures, the Medical College Admissions Test and the undergraduate grade point average. The students were in the classes of 1986 and 1987 at Southern Illinois University School of Medicine. The correlations of the admissions measures with clinical performances were quite weak, and none of the admissions measures consistently showed a clear advantage as a predictor of clinical performance. Correlations of the admissions measures with scores on National Board of Medical Examiners (NBME) Part I and Part II examinations were small to moderate, although somewhat larger than the correlations with clinical performances. Correlations were corrected for attenuation due to differential unreliabilities of the clinical examination results and the scores on NBME examinations, and for restriction of range due to the stringent medical school selection process. Corrected correlations were small to moderate and showed the same pattern as the uncorrected ones. The study documents that traditional admissions measures are useful for selecting students who will perform effectively in clinical as well as basic science settings.