Positive psychological interventions for substance use, addiction and recovery: An updated systematic review and meta-analysis.

Aims: The present systematic review and meta-analysis synthesized the literature of positive psychological interventions (PPIs) for substance use and addiction recovery from 2010 to 2023, specifically examining intervention characteristics, outcome measurement, study rigor, feasibility/acceptability and efficacy (Prospero ID CRD42023392299).

Methods: We searched PubMed, PsycInfo and Web of Science for peer-reviewed papers in English, published between 2010 and 2023, that applied a PPI to people who used substances or were in addiction recovery. We also manually searched Google Scholar, ResearchGate and reference lists of publications. The Mixed Methods Appraisal Tool was used to assess study quality and risk of bias. We conducted meta-analyses of the effects of PPIs from eight full-scale randomized clinical trials (RCTs) (i.e. RCTs with treatment groups larger than 50 participants) that measured positive psychological outcomes (n = 5 RCTs; 12 interventions) and substance use outcomes (n = 6 RCTs; 9 interventions); all other outcomes were presented descriptively.

Results: The systematic search yielded 30 eligible publications across 6 countries (14/30 from United States), that evaluated 36 individual PPIs. Nineteen articles reported randomized studies comparing a PPI with one or more control condition (eight full-scale RCTs, or trials assigning 50 or more participants to the intervention condition) and the remaining 11 were single-arm studies. PPIs varied regarding duration, mode of delivery and content. Feasibility and acceptability ratings of PPIs were positive across studies. Meta-analyses revealed a small, nonsignificant effect of PPIs on positive psychological outcomes [d = 0.23, 95% confidence interval (CI) = -0.06 to 0.52, P = 0.12] and a very small, nonsignificant effect on substance use outcomes (d = 0.11; 95% CI = -0.05 to 0.27, P = 0.19). Ten out of 30 (30%) studies received a strong quality rating.

Conclusions: Positive psychological interventions appear to be feasible and engaging, with mixed efficacy, for people who use substances or are in recovery.