Contingency management for unhealthy alcohol use: A systematic review and meta-analysis

Unhealthy alcohol use (UAU) describes a continuum of drinking behaviors ranging from risky consumption to severe alcohol use disorder (AUD). Despite its high prevalence, most individuals across this spectrum remain untreated. Contingency management (CM), a behavioral intervention utilizing reward-based incentives, effectively promotes behavior change in various substance use disorders but remains insufficiently studied across the full UAU spectrum. This systematic review and meta-analysis assesses the efficacy and clinical utility of CM for reducing alcohol use among individuals with UAU.

We comprehensively searched MEDLINE, EMBASE, PsycINFO, Scopus, and Cochrane Central through February 2025 for randomized and non-randomized trials comparing CM to treatment-as-usual or non-contingent rewards in adults with UAU. Eligible studies reported at least one objective measure of alcohol use. The primary outcome was a reduction in alcohol consumption. Meta-analyses were performed using the Generic Inverse Variance method (RevMan 5.4), with statistical significance set at p < 0.05. Heterogeneity was evaluated using Cochran's Q and I² statistics, and the risk of bias was assessed with Cochrane Risk of Bias 2 and ROBINS-I tools.

Twenty-nine studies (21 randomized controlled trials and 8 non-randomized studies; n = 2615; mean age = 41.0 years; 30.3% female) were included. CM significantly increased alcohol-negative samples (OR = 3.07, 95% CI: 2.43-3.87) and alcohol-free days (OR = 3.97, 95% CI: 1.74-9.08). CM was also effective in reducing self-reported alcohol consumption and concurrent nicotine and stimulant use. However, it did not significantly improve continuous abstinence duration (SMD = 0.88, 95% CI: -0.34 to 2.10).

This systematic review and meta-analysis demonstrates that CM effectively reduces alcohol use among adults with UAU. Given its adaptability and scalability, CM represents a promising intervention, addressing an important gap in evidence-based approaches for early intervention, harm reduction, and broader treatment of alcohol-related problems.