The survey data are designed to be used for the investigation of a broad set of topics relevant to understanding the ageing process.
Both objective and subjective data are collected covering themes such as health trajectories, disability and healthy life expectancy, the determinants of economic position in older age; the links between economic position, physical health, cognition and mental health; the nature and timing of retirement and post-retirement, labour market activity; household and family structure, social networks and social supports; patterns, determinants and consequences of social, civic and cultural participation and predictors of well-being.
Other components of the study include: a nurse visit involving measurements of physical function, anthropometric measurements and blood/saliva samples; a life-history interview collecting information on lifetime family circumstances, place of residence, employment and major health events prior to the baseline interview; and an end of life interview, initially adapted from US Health and Retirement Study (HRS), carried out by close friends/relatives of an eligible ELSA respondent who has died to collect information about the respondent's circumstances in the period since the final interview and their death.
ELSA is now part of a growing network of longitudinal ageing studies around the world which provide national data on ageing as well as the opportunity for cross-national comparisons: ELSA and HRS data were used to directly compare measures of health, income, and education amongst 55- to 64-year-olds in England and the US.
Biomarker data confirmed that these differences in disease were real and not a result of differential reporting behaviour across countries.