Medical data were collected from the charts of the subjects, and all patients were interviewed using the Childrens Hospital Adolescent Risk Profile Interview. The areas of risk contribution examined were the home, education, activities/affect, drug use, and sex/suicide. Of the 765 patients, 110 were self-identified runaways, and 655 were nonrunaways. Based on the findings, runaway street youth are at greater risk for a wide variety of medical problems and of health-compromising behaviors, including suicide and depression, prostitution, and drug use. The high level of intravenous drug use reported by the runaways, in addition to the reported involvement in prostitution and the greater likelihood of gay or bisexual lifestyle, places this group in a high-risk category for contracting and transmitting AIDS (acquired immune deficiency syndrome). There was also a high percentage of sexual abuse among the runaways. 3 tables and 10 references. (Author abstract modified)