Association of Cannabis Outcome Expectancies with Recreational Cannabis Use-A Meta-Analysis

Abstract The present meta-analysis synthesizes research on the associations between cannabis outcome expectancies and patterns of recreational cannabis use. A systematic search of electronic databases—PsycInfo, Medline, PSYNDEX, Web of Science, and Google Scholar—identified 110 studies that provided data from 65,933 respondents. Multi-level meta-analysis with random effects model was computed. Positive outcome expectancies were associated with higher levels of concurrent cannabis use and increased use over time The reverse was found for global negative outcome expectancies. Tension-reduction expectancies had the strongest concurrent association with substance use. The strength of the associations between expectancies and level of cannabis use varied, partly due to age, percentage of consumers, use of clinical versus non-clinical samples, and whether the focus was on frequency/quantity of use versus substance use disorder. Our results suggest that outcome expectancies are a relevant target for preventing and reducing cannabis use. More longitudinal research and more studies from non-Western countries are needed.