Attrition and health in ageing studies: Evidence from ELSA and HRS.

This paper investigates the characteristics associated with attrition in the English Longitudinal Study of Ageing (ELSA) and the Health and Retirement Study (HRS), with a particular focus on whether attrition is systematically related to health outcomes and socio-economic status. Our focus is on the attrition of living respondents, not attrition through death, and respondents who died are therefore excluded from our analysis. We have three main results. Firstly, raw attrition is substantially higher in ELSA than in HRS, but whether this is primarily due to differences in the administration of the two surveys, or to other unobserved differences between England and the U.S. is not clear from the available evidence. Second, these differential attrition rates do not change the core conclusions regarding comparisons between the two countries of health and socioeconomic status. Finally, very few observable characteristics predict attrition in either study among respondents in their seventies. Among respondents aged 55-64, wealth appears to predict attrition in the U.S. (but not in England), and low education predicts attrition in England (but not the U.S.). Since the more serious attrition problem exists in ELSA, we conduct additional analysis of attrition in that survey. We find that respondents’ level of numeracy strongly predicts attrition, but this does not account for the education gradient in attrition in ELSA.