risk due to interaction (RERI) of zero would indicate there is no interaction on the additive scale (i.e., perfect additivity). A RERI >0 indicates positive interaction on an additive scale, whereas a RERI <0 indicates negative interaction on an additive scale. For all a priori hypotheses, we used a p-value threshold of p <0.05 for inference criteria. All analyses were conducted separately for EA and AA samples to accommodate the inclusion of the polygenic scores.
