Rates of prostate cancer screening are known to vary among the major ethnic groups. However, likely variations in screening behavior among ethnic subpopulations and the likely role of psychological characteristics remain understudied. We examined differences in prostate cancer screening among samples of 44 men from each of seven ethnic groups (N = 308; U.S.-born European Americans, U.S.-born African Americans, men from the English-speaking Caribbean, Haitians, Dominicans, Puerto Ricans, and Eastern Europeans) and the associations among trait fear, emotion regulatory characteristics, and screening. As expected, there were differences in the frequency of both digital rectal exam (DRE) and prostate-specific antigen (PSA) tests among the groups, even when demographic factors and access were controlled. Haitian men reported fewer DRE and PSA tests than either U.S.-born European American or Dominican men, and immigrant Eastern European men reported fewer tests than U.S.-born European Americans; consistent with prior research, U.S.-born African Americans differed from U.S.-born European Americans for DRE but not PSA frequency. Second, the addition of trait fear significantly improved model fit, as did the inclusion of a quadratic, inverted U, trait fear term, even where demographics, access, and ethnicity were controlled. Trait fear did not interact with ethnicity, suggesting its effect may operate equally across groups, and adding patterns of information processing and emotion regulation to the model did not improve model fit. Overall, our data suggest that fear is among the key psychological determinants of male screening behavior and would be usefully considered in models designed to increase male screening frequency. (Cancer Epidemiol Biomarkers Prev 2006;15(2):228 -37) Prostate cancer is the second leading cause of cancer death among American men (1); there are striking ethnic differences in both its incidence and mortality (2). Compared with both European American (172.9 of 100,000) and Hispanic men (127.6 of 100,000), African American men (275.3 of 100,000) have the highest incidence of prostate cancer in the United States (3) and more than twice the mortality rate of European Americans (2). Conversely, although the incidence rates between 1995 and 1999 were f20% lower among Hispanic men, prostate cancer remains the most commonly diagnosed cancer and the second leading cause of cancer death within this group (4).Scientists know almost nothing about prostate cancer in Caribbean subpopulations. Research has, however, indicated that Jamaican men (who are often classified as ''African American'') may have an incidence rate that exceeds that of U.S.-born African Americans. One study of 2,484 men in Trinidad and Tobago, a major source of English-speaking Caribbean immigrants to the United States, suggested that the rate of prostate cancer may be as high as 10% (5), with a high number of abnormal screening findings (6). Research in Kingston, Jamaica likewise suggests that the incidence may be as high as 304...