Brief Interventions in Medical Settings Did Not Reduce Cannabis Use

Across 17 RCTs, brief drug interventions showed no significant short-term effects on cannabis use (OR=1.20), consumption level (g=0.01), or severity (g=0.13). Long-term effects were also non-significant. However, sensitivity analyses found that interventions delivered specifically in emergency departments showed small but significant reductions in long-term cannabis consumption.

Systematic review and meta-analysis of 17 randomized controlled trials comparing brief drug interventions to control conditions in general medical settings. Mixed effects meta-regression examined variability across intervention characteristics including booster sessions, delivery setting, target, and population.

Brief interventions work well for alcohol, so they have been widely adapted for cannabis. This meta-analysis shows they are not effective for cannabis in most medical settings, redirecting efforts toward settings (like EDs) where they may work.

The assumption that what works for alcohol will work for cannabis does not hold for brief interventions. Cannabis use may require different intervention approaches, or may respond better in specific settings like emergency departments where motivation for change is higher.

Heterogeneity in intervention designs across studies. Some trials had small sample sizes. Could not fully assess all potential moderators. The ED finding came from sensitivity analyses and needs confirmation.