The evolution of health over the life cycle

We construct a unified objective measure of health status: the frailty index, defined as the cumulative sum of all adverse health indicators observed for an individual. Using this index, we document four stylized facts on health dynamics over the life cycle and show that they are robust to other ways of constructing the index. We also compare the frailty index with self-reported health status and find significant differences in their dynamics and ability to predict health-related outcomes. Finally, we propose and estimate a stochastic process for frailty dynamics over the life cycle accounting for mortality bias. Our frailty measure and dynamic process can be used to study the evolution of health over the life cycle and its economic implications. (c) 2021 Elsevier Inc. All rights reserved.