Contingency management for monosubstance use disorders: Systematic review and assessment of predicted versus obtained effects.

Contingency management (CM) is notably successful as a substance use disorder treatment and is most effective when targeting monosubstance use. Evidence suggests the effects of CM exceed predictions based on the value of the incentives delivered for monosubstance abstinence. In this systematic review, we examine common variations of CM interventions applied to a single substance to determine what factors may contribute to the larger effect. Our results show that CM produced moderate to large effect sizes when single drugs were targeted, with stable effects over time. We also found that interventions targeting cocaine abstinence overwhelmingly outperformed their predicted effect, whereas interventions for smoking cessation did not. Thus, incentives alone may not account for the success of CM, at least when applied to stimulant use disorder. We propose other potential sources of the effect including social reinforcement and the specific parameters of the reinforcement schedule.