 The data in  Table 1  can be translated into success or recovery rates, showing that treated men have a higher recovery rate than untreated men (roughly 61% vs. 57%), and the same for women (44% vs. 40%). Two observations are key to understanding why this positive association vanishes in the aggregate data. First, the recovery rate of untreated men is still higher than the recovery rate of women who receive treatment (57% vs. 44%), suggesting that not only treatment, but also gender is a relevant predictor of recovery. Second, while the treatment group is majority female (27 vs. 13), the control group is majority male (7 vs. 5). Speaking informally, the lack of population-level correlation between treatment and recovery results from men being both (i) more likely to recover from the treatment, and (ii) less likely to be in the treatment group.