Fig. 3: Moderate, but not heavy, cannabis use (CU) was associated with better decision-making in people with bipolar disorder (BD).

a A significant BD status × CU frequency interaction was detected on total IGT net difference score (F(1,78) = 4.978; p = 0.009; effect size [\({\eta }^{2}\) = 0.113]). Among the healthy comparison (HC) groups, both moderate and heavy CU was associated with worse IGT performance. The BD + moderate CU group, but not the BD + Heavy CU group, exhibited significantly higher IGT scores (safer decision-making) compared to the BD group. Data presented as median, interquartile range and individual data points. Orange symbols indicate males, yellow symbols indicate females. b Pairwise comparison test statistics for BD × CU frequency groups.