College student marijuana involvement: Perceptions, use, and consequences across 11 college campuses.

Background: Marijuana is currently the most commonly used illicit drug in the United States, and with the movement toward legalization of recreational marijuana, the country faces numerous issues regarding policy, prevention, and treatment of marijuana use. The present study examines the prevalence of marijuana use and consequences and compares users and non-users on a wide range of other marijuana-related constructs among college students across 11 universities.

Method: Participants included 8141 college students recruited from the psychology department participant pools of 11 universities throughout the US, including four major regions of the US (West, South, Midwest, Northeast) and states with varying policies regarding the legality of marijuana use.

Results: We observed marijuana use rates similar to representative samples of young adults and college students (i.e., 53.3% lifetime marijuana users, 26.2% past month marijuana users). About 1 in 10 past month marijuana users experienced no consequences from their use, whereas nearly 1 in 10 experienced 19 or more consequences. Lifetime marijuana users had more positive perceptions of marijuana compared to non-users on a wide-range of marijuana-related constructs.

Conclusions: We report descriptive statistics on a wide range of marijuana-related variables. We hope that these data provide a useful baseline prior to increased legalization of recreational marijuana use. Multi-site studies like this one are needed to study the risky and protective factors for problematic marijuana use. These findings can inform interventions and public policy.