Results of individual evaluations of four successive classes of first-year medical students' performance in a communication and interviewing skills curriculum were studied using meta-analysis. Carkhuff's (1969) Standard Indexes of Discrimination (DI) and Communication (CI) were administered before and after course completion. Enrollment in the four successive classes was 46, 43, 42, and 72. Data were analyzed using combined tests and measures of effect size. The basic conclusion was that this curriculum produced large gains on two standardized measures. It was found that the performance by an average student improved 1.37 standard deviation units on the DI and 2.55 units on the CI from pre- to posttesting. Larger effects were associated with both earlier graduating classes and traditional students (versus students in a combined six-year bachelor of science/M.D. program). It is concluded that the curriculum may be compared vis-a-vis student performance measures from year to year, as well as over all the years it is offered. Combining and synthesizing these individual class findings permits greater generalizability and confidence in the evaluation results of the program than do individual results based on smaller sample sizes. (SW)