Progressive legalization of medical and recreational cannabis markets at the state-level has led to rapid growth of medical and recreational cannabis markets and to product diversification with emerging products having high concentrations of delta-9-tetrahydrocannabinol. Research on these products is still limited and the evidence available for policy formulation is diminished by methodological limitations. As a step towards addressing these limitations, the Colorado School of Public Health convened a multidisciplinary workshop that addressed four areas of cannabis research: epidemiological, clinical, surveillance, and policy. Workshop participants provided recommendations in each area to advance research on cannabis to make it more informative for decision-making on key policy topics. Emphasis was placed on assessment of use of cannabis products by study participants.
Rapid changes in the legalized canna-bis market have led to the predominance of high-concentration delta-9-tetrahydrocannabinol (THC) cannabis products. In this paper we systematically review associations of high-concentration THC cannabis products with mental health outcomes.
In conducting a scoping review on the health effects of high-concentration cannabis products, we have uncovered pervasive methodological shortcomings within the cannabis literature. This review begins by defining the “causal effect” of interest for public health and delineating the desirable features of study design that can address crucial questions pertaining to public health and policy. We further delve into the methodological complexities inherent in studying the health effects of high-concentration cannabis products, describing challenges associated with the measurement of exposures and outcomes, confounding, selection bias, and the generalizability of findings. We introduce causal inference methods to mitigate potential biases in observational cannabis use studies. We identify specific areas that necessitate further development and investigation to deepen our understanding of this topic. Finally, this review extends actionable recommendations, serving as a roadmap for upcoming research initiatives in this domain.
We describe the scoping review on high-concentration cannabis with the dual goals of documenting the utility of this approach to evidence identification and introducing the evidence map to the public health community. The objectives of the scoping review were to (1) identify and describe human studies that explore the relationship of high-concentration cannabis products with any health outcomes and (2) create an interactive evidence map of included studies to facilitate further analysis.
