Even though PRS pT < 0.01 was associated with DSM4AD at α < 1.1e-3, the difference in AUC attributable to the addition of the PRS was modest (AUC-covariates = 0.710; AUC-covariates+PRS = 0.713; equality test χ2 = 6.62, p = 0.01). Results for alcohol use were far stronger: the AUC in a model where PRS alone predicted alcohol use was 0.57. Even in comparison to the model with covariates alone (AUC=0.688), addition of PRS resulted in a statistically significant increase in prediction of alcohol use (AUC = 0.70; equality test χ2 = 9.36, p = 0.0022). Youden’s J was 0.11 (sensitivity = 0.49, specificity = 0.62) and a PRS cut-point of 0.0524 was determined to maximize classification, but at a weak AUC of 0.56.
