What Can Be Learned About Aging Clocks from Existing Clinical Trial Data for Longevity Interventions?

From the abstract

Aging clocks can be readily produced by using what are by now well established machine learning techniques on any body of biological data that changes with age. Omics data is favored, as there are a great many databases of such data for large study populations, but clocks have been made using clinical chemistry results from simple blood tests, imaging data, and many other items. A clock is calibrated to predict age in the reference population, and when used on people outside that reference popul