Evaluating medical student obstetrics and gynecology clerkship performance: which assessment tools are most reliable?

Objective: This study was undertaken to investigate medical student performance on an obstetrics and gynecology (Ob-Gyn) core clerkship to determine the most discriminating measures of student performance.

Study Design: Four-hundred twenty-one clinical clerks were assessed with the use of 46 performance indicators in 4 different categories. Final Scores were weighted: (1) Clinical Performance = 60%, (2) Formal Presentation = 10%, (3) Oral Examination = 10%, and (4) National Board of Medical Examiners (NBME) Subject Test score = 20%.

Results: A total of 17,023 scores were examined. Final Scores were normally distributed. Clinical Performance and Formal Presentation scores were highly skewed, explaining 35% and 5% of the Final Score variance, respectively. Oral Examination scores were slightly skewed, explaining 17% of the variance. The NBME Subject Test score was the only normally distributed performance indicator and, despite comprising only 20% of Final Scores, was the most highly correlated ( R = 0.86), explaining 74% of the variance.

Conclusion: Despite their minor weighting in our grading system, NBME Subject Test scores were very highly correlated with overall clinical clerkship performance. By combining written Subject Test and Oral Examination scores, 91% of the variance in Final Scores can be explained.