In Add Health and COGA, we performed out-of-sample validation of EXT by modeling a latent phenotypic externalizing factor corresponding to the seven Genomic SEM phenotypes (Supplementary Information section 5.2.3) (Supplementary Tables 27–28). In Add Health, COGA, PNC, and the UKB siblings hold-out cohort, we performed exploratory analyses with a range of preregistered phenotypes from various domains (Supplementary Tables 29–31, 34). In BioVU, we performed a phenome-wide association study (PheWAS) of medical outcomes by fitting a logistic regression to 1,335 case/control disease “phecodes”83 (N = 66,915) (Supplementary Table 32), adjusted for sex, median age in the EHR data, and the first 10 genetic PCs.
