This project utilized existing high quality data from a number of prospective cohort studies from various countries. Currently data from Finland, France, Germany, Norway, the UK and the USA, that have followed people from midlife to retirement, and that are publicly available with permission, has been used. The data on work-related physical and psychosocial factors from midlife, lifestyle factors, health behaviours, socio-demographic factors and health such as musculoskeletal disorders, functional ability, etc. will be studied as outcomes. The aim of this research project is to study the effect of midlife working conditions as core determinants of health at old age using meta-analytical approaches of individual participant data (IPD).