Figure 2a and 2b represent the meta-analyses for genetic contributions to problematic cannabis use for males and females, respectively. Again, the bottom line shows the results of our meta-analysis. The point estimates from the meta-analyses generally fall within the reported confidence intervals of the estimates from the source studies, suggesting reasonable homogeneity of studies. Exceptions were Agrawal et al. (47), where the confidence intervals are particularly narrow, and McGue et al. (27) and Tsuang et al. (48), where confidence intervals were not reported but estimated by us.
