The larger, biracial cohort and the longer follow‐up interval in ARIC‐NCS allowed us to attempt to replicate the risk models previously developed in the MCSA and FHS7 and to examine several covariates including age, race, sex, education, apolipoprotein E (APOE) genotype, and initial diagnosis of MCI to ascertain the generalizability of dementia risk prediction using domain‐based cognitive characterization. This evidence concerns the gene APOE and dementia.