Please use this link to access this publication. Abstract Objective: Cannabis markets are evolving in terms of greater diversity and potency of products. The current study examined changes in cannabis use and modes of consumption among 16- to 19-year-olds in three markets with different regulatory frameworks: England, Canada, and the United States (US). Methods: Repeat cross-sectional online surveys were conducted in 2017, 2018, and 2019, with samples of 16- to 19-year-olds recruited from commercial panels in Canada (n = 11,779), England (n = 11,117), and the US (n = 11,869). Regression models examined changes in the prevalence of any cannabis use and use of...

IMPORTANCE Vaporization is an increasingly popular method for cannabis administration,and policy changes have increased adult access to cannabis drastically.Controlled examinations of cannabis vaporization among adults with infrequent current cannabis use patterns(>30 day ssince lastuse)are needed. OBJECTIVE: To evaluate the acute dose effects of smoked and vaporized cannabis using controlled administration methods. DESIGN,SETTING,AND PARTICIPANTS This within-participant,double-blind,crossover study was conducted from June 2016 to January 2017 at the Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, and included 17 healthy adults. Six smoked and vaporized outpatient experimental sessions (1-week wash out between sessions)were completed in clusters (order counterbalanced across participants);dose order was randomized within...