Figure 1

A schematic illustration of the participant selection process used in the present study. (a) Of the 1,125,691 total participants, 60,957 participants with depression were matched with 243,828 control I participants for age, group, sex, income group, region of residence, and past medical histories. (b) Of the 1,125,691 total participants, 133,089 participants with GERD were matched with 266,178 control II participants for age, group, sex, income group, region of residence, and past medical histories.