Using correlation ratios and analysis of variance, several potential variability factors in student clerkship performance were examined. Comparisons are made between clerkship clinical sites for scores on written work, clinical work, and examination scores, and for factors such as the amount of patient and faculty contact. A small amount of grade variance is due to clerkship site. Correlations between scores on clinical skills and examination scores were low, consistent with the idea that grades of clinical performance and performance on examinations measure different dimensions of student ability. The relevance for clerkship planning and grading equity is discussed.Abstract Teaser