Methodological challenges and actionable recommendations in studying the health effects of high-concentration THC products.

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 paper 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 paper extends actionable recommendations, serving as a roadmap for upcoming research initiatives in this domain.