Participants were followed for up to 22 years (M = 12, SD = 6, range 1–22). The onset of clinical AD was diagnosed in 90 individuals within an average of 8 years (SD = 4, range 1–18) from the baseline personality assessment. Table 1 presents the initial demographic characteristics of the overall sample and separately for the group of participants who developed AD and those who did not. The incident dementia group was significantly older and more likely to be white. This effect of ethnicity was due partly to the younger age of the minority group (54.8 vs. 57.2, p = 0.005), because they were recruited later in the study. There were no significant differences between the groups on education or sex.
