Effectiveness of continuing care interventions for substance abusers. Implications for the study of long-term treatment effects.

Substance-abusing patients are frequently urged to participate in lower intensity continuing care interventions, also known as "stepdown care" or "aftercare," following an initial phase of treatment. Since 1988, 15 controlled studies of continuing care for alcohol or drug abuse have been published, with follow-up data on substance use presented in 14 of these studies. In the studies that featured an active control condition, only 1 of 7 yielded positive findings. In the studies that featured a minimal- or no-treatment control, 3 of 7 studies yielded positive findings. The relative paucity of continuing care studies, coupled with the lack of stronger evidence of clinical effectiveness, provides a convincing rationale for conducting evaluations of continuing interventions, as well as evaluations of combinations of various primary and continuing interventions. Methodological issues in the evaluation of continuing care and potential research questions that could be addressed in long-term follow-up studies are outlined and discussed.