Cohort profile: the GAZEL Cohort Study

Abstract

Électricité de France-Gaz de France (EDF-GDF) is the only utility firm in France involved in production, transmission and distribution of energy. For several reasons, EDF-GDF is a unique setting for epidemiology. The company employs about 150 000 workers in all regions of France, from large cities to small villages; there is a wide socioeconomic range of occupational positions, including white and blue-collars workers. The workforce is very stable: due to their civil servant-like status, employees almost never leave the company and are not lost to follow-up even after retirement, since retirement benefits are paid by the company itself. An extensive human resources system allows for a complete follow-up of the workers, even when they retire. EDF-GDF has its own Occupational Health and Social Security system; about 300 physicians work for the company and are responsible for the health surveillance of the workers.