Living Longer and Healthier? An Advancement of Methodology and Understanding on Health Expectancy

Abstract

Life expectancy has been increasing in many countries in the past decades. Health expectancy, as a helpful indicator to gauge the well-being of older adults and the sustainability of the future economy and public welfare policies, however, does not always show the same increase. These diverging patterns might result in greater numbers of elderly requiring healthcare and living in compromised quality of life. Multistate life table models are widely used to compute health expectancy from the survey, but they require strict and simple assumptions, which could produce results deviating from the actual dynamics of health over the life course. As many developed and developing societies are transitioning or soon to be transitioning to aging societies, it is imperative to produce more realistic health expectancies accounting for life-course dynamics. The primary objective of this dissertation is to improve multistate life table model and to better understand and estimate the healthy life expectancy. Simultaneously, substantive findings may emerge by applying improved methods across populations or subpopulations. This dissertation would explore and develop novel methods related to healthy life expectancy over seven chapters. Chapter 1 provides the background information, literature review, methodology, and conceptual framework, followed by five substantive chapters and a conclusion. Chapter 2, which is the first analytical chapter, explores the interactions between morbidity and disability and uncovers a dynamic equilibrium in the change of health expectancy across US birth cohorts. Chapter 3 proposes a new analytical method to decompose the components of differences or changes in health expectancy calculated from multistate models. Chapter 4 introduced a flexible method to estimate health expectancy with more than one time-varying variable to address a major limitation of the current multistate model. Chapter 5 investigates duration dependency in healthy life expectancy estimates by adopting a new semi-Markov model. Finally, Chapter 6 concludes with a discussion of the contributions, research limitations, and suggestions for future studies. Show more