Figure 2

Random-effects meta-analysis of N = 15 studies on anxiety vs. cannabis use/no use. Notes: The forest plot (top) shows the effect size (OR) in each study, the weight of each study (size of the box), and the 95% CI (the horizontal line through each box). The overall mean weighted OR is depicted as the centre of the diamond and its horizontal edges are the 95% CI. Since the diamond did not cross the line of no effect (OR=1), there was an overall positive association between anxiety and cannabis use in N=15 studies (overall mean weighted OR=1.24, 95% CI: 1.06-1.45). The funnel plot (bottom) shows the distribution of the individual effect sizes around the overall mean weighted OR (unfilled diamond). The trim-and-fill analysis revealed that the plot was symmetrical (the recomputed overall mean weighted OR depicted as the filled diamond overlaps with the unfilled diamond) suggesting that there was little evidence for a publication bias in the current analysis.