Handgrip strength for predicting incident ADL disability in older adults with arthritis: a multi-cohort external validation study

Handgrip strength is an established marker of functional health, but a prognostic association does not guarantee that its incremental predictive value or derived absolute risks transfer across populations. We evaluated the cross-cohort transportability of handgrip-based prediction of incident disability in basic activities of daily living (ADL) and whether alternative handgrip representations improved external performance.