Exposure to methadone programs and heroin use.

The aims of this study were to: (a) assess the effects of various patterns of exposure to methadone programs on heroin use; (b) assess the effects of other patient, program, and treatment variables; and (c) identify variables that promote the type of exposure to methadone programs that is most effective for reducing heroin use. The sample was 526 patients who were admitted from 1979 to 1981 into 17 methadone programs that participated in the Treatment Outcome Prospective Study. The study differs from previous research in that it addresses the time that patients spent in methadone programs during the follow-up period in defining exposure patterns. Heroin use was lowest among patients who were continuously exposed to methadone programs. Retention was highest among patients who attended programs that informed them of their methadone dose levels, were easy to access, and provided them with high quality social services.