BACKGROUND: Cannabis is consumed in various social and environmental settings, and such contexts may be important predictors of subjective effects. The aim of this systematic review and meta-analysis was to examine the relationship between contextual factors and subjective effects of cannabis.

METHODS: A PRISMA-guided search of MEDLINE, Embase, PsycINFO, Global Health, and Google Scholar yielded 29 studies.

RESULTS: Study type (Ecological Momentary Assessment or Experimental) was a significant predictor of intoxication effects, and experimental studies had a greater pooled effect size (z =.296,95% CI [.132,.478], p=.004) than Ecological Momentary Assessment (EMA) studies (z =.071,95% CI [.011,.130], p =.02). Contextual conditions (environment, social group, expectancy, time of day, day of week) were not significant predictors of cannabis effects.

CONCLUSION: Findings did not point to a significant association between contextual conditions and subjective effects. However, as current literature is methodologically weak, it may be premature to conclude that subjective effects are not shaped by contextual factors. In view of policy and therapeutic implications, replications and study refinements are recommended.