All non-demented ADNI participants who completed a baseline neuropsychological assessment were considered for analyses. Of the 1,397 participants considered for inclusion, 57 were excluded due to the absence of follow-up data. The final sample consisted of 1,340 participants. Of these participants, 616 were determined to meet criteria for MCI based on Jak/Bondi actuarial neuropsychological diagnostic method [14 (link),15 (link)]. Participants were classified as MCI if they 1) performed >1SD below the age/education/sex-adjusted mean on two measures within the same cognitive domain, or 2) performed >1SD below the demographically-adjusted mean on at least one measure across all three sampled cognitive domains, or 3) were rated by a study partner to have a Functional Activities Questionnaire (FAQ) score > 5, suggesting functional difficulties across at least two areas of functioning (see Figure 1). The remaining 724 participants were determined to be cognitively normal. We applied the Jak/Bondi criteria at each of the participants’ follow-up visits (6-, 12-, 24-, 36-, 48-, 60-, 72-, 84-, 96-, 108-, and 120-months after baseline) to determine whether or not, and if so at what point, they progressed to MCI. We also tracked whether participants progressed to dementia based on ADNI’s AD criteria: 1) subjective memory complaint reported by the subject, study partner, or clinician; 2) abnormal memory function defined by scoring below the education-adjusted cutoff on Story A of Logical Memory II from the Wechsler Memory Scale–Revised; 3) MMSE score < 27; 4) Clinical Dementia Rating score of 0.5 or 1.0; 4) met NINCDS/ADRDA criteria for probable AD [16 (link)]. A proportion of the sample underwent a lumbar puncture at baseline (MCI n=434; cognitively normal n=532); this subset was used for analyses involving CSF markers.