CONSTANCES is the largest French population based-cohort.
It is designed as a randomly selected representative sample of French adults aged 18-69 years at study inception; 200,000 subjects will be included over a five-year period. The selected subjects are invited to attend one of the 17 participating Health Screening Centres (HSCs). The follow-up includes a yearly self-administered questionnaire, a periodic visit to an HSC.
Constances is also innovative by the wealth of data collected by linkage to multiple administrative databases.