Abstract: | The Drug Abuse Treatment Outcome Study (DATOS) collected 1-year follow-up outcomes for 2,966 clients in outpatient methadone (OMT), long-term residential (LTR), outpatient drug-free (ODF), and short-term inpatient (STI) programs in 1991–1993. LTR, STI, and ODF clients reported 50% less weekly or daily cocaine use in the follow-up year than in the preadmission year. Reductions were greater (p? |