Simultaneous alcohol and marijuana use among underage young adults in the United States

OBJECTIVE: The current study examines the prevalence, stability, and correlates of simultaneous alcohol and marijuana (SAM) use among underage US young adults, a population at high risk for participating in this behavior. METHOD: Analyses used data from 1,719 respondents (46.8% men) who participated in the nationally representative 12(th)-grade Monitoring the Future study and provided responses to SAM use items at longitudinal follow-up at modal ages 19/20 between 2007 and 2016. Prevalence estimates and covariate associations with SAM use were estimated. RESULTS: SAM use prevalence at modal age 19/20 was 22.5%. Multivariable models indicated that odds of age 19/20 SAM use were significantly (p