To test the robustness of six selected risk factors (TBI, APOE e4/e4, hypertension, diabetes, depression, and education) from the previous specification curve analyses, we executed 3912 multivariate logistic regression models with different combinations of the selected risk factors (while adjusting for age, gender, and ethnicity) (Fig. 3 and Table 2). Here, APOE is linked to Hypertension.