Getting to the Roots of Long-Term Care Needs: A Regression Tree Analysis

This paper investigates the effects of individual and environmental determinants on physical and cognitive impairment of Europeans aged 50 and older using data drawn from the Survey of Health Aging and Retirement in Europe (SHARE). The aim is to understand the different paths that need-related determinants of long-term care might take across individuals. As dependent variables, we consider several measures of physical and cognitive disability which are regressed on a list of covariates which includes biological, health, behavioural, socio-demographic and early-life conditions of individuals. We adopt a methodology that combines the structure of random effects models for longitudinal data with the flexibility of a tree regression method. We show the existence of clusters in the main determinants of functional decline (physical and cognitive). Our findings are in line with the existing literature, but, at the same time, we further characterize previous evidence: 1) cognitive impairment, measured by the results of a memory test, strongly depends on educational attainments, age and respondents’ country of residence; 2) physical impairment, measured through the loss of handgrip strength, basic and instrumental activities of daily living (ADLs, IADLs) and mobility, strongly depends on health and behavioural factors.