Trustworthy ML/AI for Aging Clocks: Preventing Systematic Prediction Bias in Biological Age Estimation
Journal:
bioRxiv
Published Date:
Jun 1, 2026
Abstract
Machine learning (ML)- and artificial intelligence (AI)-based aging clocks are increasingly used to quantify physiological and molecular aging from omics and medical imaging data as distinct from chronological age. Here, we characterize a fundamental but underappreciated computational limitation of commonly used ML/AI regression models: systematic prediction bias and its propagation to downstream association estimates. We demonstrate that systematic prediction bias can distort, and in some cases reverse, biomedical conclusions drawn from aging-clock analyses. For example, it can produce spurious associations suggesting that older predicted brain age is linked to better cognitive performance, or that older epigenetic age is associated with better kidney function. To address this problem, we introduce a principled and broadly applicable ML/AI regression framework based on constrained optimization, ensuring trustworthy aging-clock estimation and biomedical inference.
