A clinically-translatable machine learning algorithm for the prediction of Alzheimer's disease conversion: further evidence of its accuracy via a transfer learning approach

M. Grassi*, D.A. Loewenstein, D. Caldirola, K. Schruers, R. Duara, G. Perna

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Background: In a previous study, we developed a highly performant and clinically-translatable machine learning algorithm for a prediction of three-year conversion to Alzheimer's disease (AD) in subjects with Mild Cognitive Impairment (MCI) and Pre-mild Cognitive Impairment. Further tests are necessary to demonstrate its accuracy when applied to subjects not used in the original training process. In this study, we aimed to provide preliminary evidence of this via a transfer learning approach. Methods: We initially employed the same baseline information (i.e. clinical and neuropsychological test scores, cardiovascular risk indexes, and a visual rating scale for brain atrophy) and the same machine learning technique (support vector machine with radial-basis function kernel) used in our previous study to retrain the algorithm to discriminate between participants with AD (n = 75) and normal cognition (n = 197). Then, the algorithm was applied to perform the original task of predicting the three-year conversion to AD in the sample of 61 MCI subjects that we used in the previous study. Results: Even after the retraining, the algorithm demonstrated a significant predictive performance in the MCI sample (AUC = 0.821, 95% CI bootstrap = 0.705-0.912, best balanced accuracy = 0.779, sensitivity = 0.852, specificity = 0.706). Conclusions: These results provide a first indirect evidence that our original algorithm can also perform relevant generalized predictions when applied to new MCI individuals. This motivates future efforts to bring the algorithm to sufficient levels of optimization and trustworthiness that will allow its application in both clinical and research settings.
Original languageEnglish
Article number1041610218001618
Pages (from-to)937-945
Number of pages9
JournalInternational Psychogeriatrics
Issue number7
Publication statusPublished - 1 Jul 2019


  • alzheimer's disease
  • atrophy
  • brain
  • clinical prediction rule
  • diagnosis
  • individuals
  • machine learning
  • mci
  • mild cognitive impairment
  • mri
  • personalized medicine
  • precision medicine
  • transfer learning
  • MRI
  • MCI
  • Alzheimer's disease

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