Prior treatment experience related to process and outcomes in DATOS.

Using data collected from cocaine-abusing patients who participated in the Drug Abuse Treatment Outcome Studies (DATOS), we contrasted patients in treatment for the first time and patients having extensive histories of prior treatment to identify factors associated with better outcomes in each group. Compared with first-timers, treatment-experienced patients had less favorable post-treatment outcomes. Indicators of early engagement in DATOS treatment predicted post-treatment abstinence for both groups. Importantly, the interaction of treatment history and several process measures affected post-treatment abstinence. For example, individual counseling and program compliance had greater impacts on abstinence among treatment repeaters in outpatient drug-free programs than for first-timers. Social support and environmental context were significantly related to abstinence. These findings confirm the importance of considering treatment process and aftercare in developing and implementing strategies to optimize treatment for patients with different treatment histories.