A 13-item questionnaire was constructed to assess risk factors for HJV infection among 476 patients newly admitted over a one year period to a state psychiatric hospital in New York City. Because psychopathology can affect patients' self-reports, the validity of the instrument was established by HIV antibody tests in a subset of 352 patients. Results of the questionnaire indicated that the 352 patients were almost equally divided between the high-risk and low-risk categories. HJV seroprevalence was .6 percent among the low-risk patients, but 14.4 percent among the high-risk patients. The findings suggest that a screening program to detect HW-positive patients should be undertaken in this population, that it should be focused on the high-risk subgroup, and that the questionnaire can be used to define that subgroup. However, results of the study may not generalize to other geographic areas.