Medical school curricula are attempting to enhance positive attitudes toward a biopsychosocial model of illness and to correct prejudicial stereotypes toward various patient groups through affective education. To explore the evaluative attitudes of first and second year medical students in the areas of trends in predispositions toward different disease populations and patient characteristics, attitude change in the first year of medical school, and experience with certain disease categories, 323 New York University Medical School students provided demographic information, completed a Likert-type attitudinal scale measuring professional distance, and responded to a patient case description which was manipulated according to four variable: sex, age, prognosis, and diagnosis (cancer, heart disease, psychiatric disorder). An analysis of the results showed that students opted to maintain greater professional distance from males compared to females, poor prognosis compared to good prognosis patients, psychiatric patients compared to cancer patients, and cancer patients compared to heart disease patients. Student class year and previous experience with the disease significantly affected attitudes, with more experienced students showing more comfort and willingness to work with certain patients, particularly cancer patients. Since differential patient preferences were observed at the onset of medical school, early educational interventions may be needed to address the potential for negative attitudes. (BL)