Storck et al Cardiovascular Risk 2025 Meta-Analysis: Limitations

"Our study has several limitations. First, cannabis exposure was poorly reported in the included studies, which prevented our meta-analysis from assessing it. Second, a significant portion of included studies was at moderate to high risk of bias, primarily due to a lack of information regarding missing data. Concerns were also raised about the risk of misclassification of exposure, particularly in studies from medical databases, which have a low sensitivity for non-medical drug use. Studies that relied on patient surveys faced substantial bias regarding exposure and outcome misclassification when patients assessed these data themselves. Furthermore, most included studies (n=19) were cross-sectional, a design providing a poor level of evidence unable to establish the causal link between outcome and exposure. Third, several of the included studies used the same data source, sometimes overlapping in the period, with the risk of including the same patients. Fourth, our data collection was limited to between 1 January 2016 and 31 January 2023."