https://arstechnica.com/gadgets/2021/03/apple-watch-could-replace-in-clinic-tests-to-measure-frailty-study-says/

A new study on the effectiveness of the Apple Watch and iPhone as tools for measuring functional capacity in patients with cardiovascular disease (CVD) has been published by researchers at Stanford University.

The study, which involved 110 participants, found that the health-monitoring capabilities in these products could supplement or replace in-clinic tests for "frailty" in patients with CVD.