Fig. 3

The average values of the receiver operating characteristic (ROC) curves, obtained for the models discussed in the “Machine learning modeling” section, are presented. The ROC curves were calculated on the test set from a ten-fold cross-validation. The analyzed classification tasks encompassed: A discrimination between subjective cognitive decline (SCD) and patients with mild cognitive impairment (MCI) or Alzheimer’s disease dementia ADD, B SCD vs ADD, C SCD vs MCI, D and MCI vs ADD. Abbreviations: RF, random forest; XGB, extreme gradient boosting; GA, genetic algorithm; SVM, support vector machine; and KNN, k-nearest neighbor