Effect of prize-based incentives on outcomes in stimulant abusers in outpatient psychosocial treatment programs: A national drug abuse treatment clinical trials network study

Abstract

Context: Contingency management interventions that provide tangible incentives based on objective indicators of drug abstinence are efficacious in improving outcomes in substance abusers, but these treatments have rarely been implemented in community-based settings. Objective: To evaluate the efficacy of an abstinence-based contingency management intervention as an addition to usual care in community treatment settings. Design: Random assignment to usual care or usual care plus abstinence-based incentives for 12 weeks. Setting: Eight community-based outpatient psychosocial drug abuse treatment programs. Participants: A total of 415 cocaine or methamphetamine users beginning outpatient substance abuse treatment. Intervention: All participants received standard care, and those assigned to the abstinence-based incentive condition also earned chances to win prizes for submitting substance-free urine samples; the chances of winning prizes increased with continuous time abstinent. Main Outcome Measures: Retention, counseling attendance, total number of substance-free samples provided, percentage of stimulant- and alcohol-free samples submitted, and longest duration of confirmed stimulant abstinence. Results: Participants assigned to the abstinence-based incentive condition remained in treatment for a mean±SD of 8.0±4.2 weeks and attended a mean±SD of 19.2±16.8 counseling sessions compared with 6.9±4.4 weeks and 15.7±14.4 sessions for those assigned to the usual care condition (P