We conducted a series of meta-analyses on subsets of the full sample using the same methods as above. Age group-specific meta-analyses were run in the cohorts of children (age < 17; GENR, TEDS, IMAGEN, BLTS; N=9,814), young adults (age ~17–18; S4S, STR; N=6,033), adults (age > 18, primarily middle-aged or older: UKB, RS, DTR, NESCOG, STSA; N=204,228), and older adults (mean age > 60, RS, DTR, STSA; N=8,323), excluding studies whose samples overlapped child/young adult and adult groups (COGENT, HiQ/HRS, GfG; N=49,792). To create independent discovery samples for use in polygenic score validation, we also conducted meta-analyses with a “leave-one-out” strategy in which summary statistics from four validation datasets were, respectively, excluded from the meta-analysis (see Polygenic Scoring, below).
