Driezen P, Gravely S, Wadsworth E, et al. - This study was undertaken to investigate if changes in cannabis use frequency were associated with smoking cessation. Between 2016 and 2018, researchers surveyed Nationally representative samples of adult cigarette smokers from Canada (n=1,455), the United States (n=892), England (n=1,416), and Australia (n=717). Smokers reported how often they used cannabis in the previous 12 months in each year. They compared reports to ascertain if cannabis use increased, remained unchanged, or decreased. In comparison with non-cannabis using smokers, smokers who increase their frequency of cannabis use have poorer smoking cessation outcomes. It will be beneficial to evaluate the impact of cannabis legalization on patterns of cannabis use, and whether this influences cigarette smoking cessation rates.