ELSA, the English Longitudinal Study of Ageing, has been in existence since 2002, when it subsumed a preceding Health & Safety Executive (HSE) study. There have now been eight ELSA waves and ELSA-9 data collection has been going on during the period 2018/19. 

ELSA’s large sample size  and its very comprehensive question inventory make it useful in both longitudinal studies (where trends and lifecourse trajectories can be identified across the multiple ELSA waves) as well as in simpler cross-sectional mode, as adopted in B60 by focusing on the ELSA Wave 7 data.

The best way to see what ELSA is concerned with is to look at the ELSA Questionnaire  or some of the many items of ELSA Documentation.