Recreational Marijuana Laws and Youth Marijuana Use

"Among 207,781 national YRBS [Youth Risk Behavioral Survey] respondents (mean [SD] age, 16.04 [1.23] years; 50.90% male), 13.35% were Black or African American, 17.09% were Hispanic, and 60.13% were non-Hispanic White. Among 1 549 075 state YRBS respondents (mean [SD] age, 16.01 [1.23] years; 50.20% male), 16.53% were Black or African American, 17.78% were Hispanic, and 58.09% were non-Hispanic White.

"Based on the national YRBS, RML [Recreational Marijuana Laws] adoption was not associated with current marijuana use (odds ratio, 0.97; 95% CI, 0.85-1.10) or frequent marijuana use (odds ratio, 0.98; 95% CI, 0.83-1.16) (Table). Estimates based on the state YRBS and estimates of the association between the first dispensary opening and marijuana use were qualitatively similar (Table). Interaction-weighted estimates were similar to their logistic regression counterparts (Table).

"Based on the national YRBS and using lead and lag indicators in place of the RML indicators, there was no association between RMLs and marijuana use during the prelegalization period (Figure), suggesting the parallel-trends assumption held. After legalization, there was no evidence of an increase in marijuana use.