The Chicago Health and Aging Project excluded individuals with Alzheimer's at baseline, low cognitive scores, and APOE 4/4 or 4/3 genotypes to focus on modifiable risk factors.

“they had no Alzheimer's disease at the outset they were all cognitively tested and the bottom 10 in of of non-ad patients in terms of cognition were excluded so we're sort of trying to take out what we think were the most susceptible uh they also excluded any patients who were four fours so if a patient is E4 you're going to see that the data are divided between E4 and non-e4 so the E4 segment is just two fours and three fours and that was about a third of the sample so a third of the sample had two four or three four and a third of the sample had no E4”