Abstract
The French work force is aging, like that of many other European countries. Projections underscore that over the next 20 years there will be a dramatic increase in the working population over 45 years. Working conditions in France tend to increase the difficulties for aging workers: the work schedules are less stable, the constraints of work rhythms become greater, etc. We are interested in the age-related selection mechanisms that may stem from the confrontation of two evolutions, aging of operators and transformations in the work situations (Molinie & Volkoff, 1994). Most studies on this subject generally rely on observation of populations in different age groups at a given date. But the selection processes can only really be detected in a dynamic framework, by incorporating observations on the assignment of wage-earners of different ages into a study of professional careers. We have been able to formulate a quantitative approach of selection mechanisms, thanks to the Health, Work, and Ageing Survey (''ESTEV''), which was based on a random sample of 21,000 wage earners followed-up by work physicians (400 in 1990, 1000 in 1995). Subjects, male and female, belonged to age groups of 5-year intervals, from 1938 to 1953. Each age cohort included about 3000 subjects for men, and about 2000 for women (Derriennic, Touranchet, & Volkoff, 1996). They were first interviewed in 1990, and again in 199 (percentage of subjects seen both times: 87%). The present study relies on 22 questions aimed at identifying the constraints or hardships that the surveyed workers have encountered in the course of their working life. In each case, the worker was asked whether he or she was presently exposed, was not now but had been exposed, or had never been exposed to the constraint.