A comparison of statistical criteria for setting optimally discriminating MCAT and GPA thresholds in medical school admissions

Teach Learn Med. 2005 Spring;17(2):149-58. doi: 10.1207/s15328015tlm1702_9.

Abstract

Background: Using Medical College Admission Test-grade point average (MCAT-GPA) scores as a threshold has the potential to address issues raised in recent Supreme Court cases, but it introduces complicated methodological issues for medical school admissions.

Purpose: To assess various statistical indexes to determine optimally discriminating thresholds for MCAT-GPA scores.

Methods: Entering classes from 1992 through 1998 (N = 752) are used to develop guidelines for cut scores that optimize discrimination between students who pass and do not pass the United States Medical Licensing Examination (USMLE) Step 1 on the first attempt.

Results: Risk differences, odds ratios, sensitivity, and specificity discriminated best for setting thresholds. Compensatory versus noncompensatory procedures both accounted for 54% of Step 1 failures, but demanded different performance requirements (noncompensatory MCAT-biological sciences = 8, physical sciences = 7, verbal reasoning = 7--sum of scores = 22; compensatory MCAT total = 24).

Conclusions: Rational and defensible intellectual achievement thresholds that are likely to comply with recent Supreme Court decisions can be set from MCAT scores and GPAs.

Publication types

  • Comparative Study

MeSH terms

  • College Admission Test*
  • Humans
  • Midwestern United States
  • Odds Ratio
  • School Admission Criteria / statistics & numerical data*
  • Schools, Medical*
  • Sensitivity and Specificity
  • Supreme Court Decisions