A French national birth cohort: the ELFE project (Etude longitudinale française depuis l’enfance). Some methodological issues

Henri Leridon, Institut National d'Études Démographiques (INED)
Claudine Pirus, Institut National d'Études Démographiques (INED)

The purpose of the Elfe project is to establish a nationally representative cohort of 20,000 children to be followed from birth to adulthood under a multidisciplinary approach. (social sciences, health and health-environment). The cohort will provide a unique source of data to analyse the development of children in their environment and the various factors interacting throughout the life course: family structure, social and physical environment, schooling, health and nutritional behaviour, etc. On the epidemiological side, we will register cumulative exposures to specific pollutants year after year and analyse their consequences on social and health inequalities. The cohort will be based on the INSEE Demographic Panel (échantillon démographique permanent, EDP). Since 1968, all citizens born on 4 specific days of the year have been included passively in the INSEE sample. The extension of this Panel to 16 days will allow us to follow a representative sample of children born in 4 different quarters of a given year (possibly 2008). The original feature of the cohort lies in this sampling frame which will make it easy to identify the children of the cohort in other statistical sources. The panel will serve as a basis for existing surveys taking place periodically and that, until now, had used different samples (perinatal surveys, health surveys at school, etc). It will also be paired up with other data sources, including those from the Social Security and the educational systems. Additional data will be collected through face-to-face interviews, telephone interviews, assessment tests, self-completed questionnaires… Biological samples will be taken at birth and possibly later. To evaluate exposure to certain pollutants, environmental sensors may be placed in the children’s homes. Furthermore, it will be possible to use data from national bases on geographic sources of pollution thanks to geocoding of the dwellings concerned.