Fig. 6: Kaplan–Meier curves of survival without conversion to AD produced by the prediction models.

We calculated a prognostic index for each subject by applying three biomarkers (IGK, TRA, and WDR37) and clinical factors to our prognosis prediction model. (a) Based on the prognostic index, we divided the samples of the discovery cohort into high- (red) and low-risk (blue) groups. The optimal cutoff values were detected by using the minimum P-value from the log-rank test and comparing the differences in survival without MCI-to-AD conversion as determined by Kaplan-Meier curves (optimal cutoff = –0.0969, minimum P = 1.94 × 10−4). (b) The adjusted model was then evaluated on the validation cohort (log-rank test P = 2.57 × 10−3).