Why the cohort was set up?CONSTANCES is a general-purpose cohort with a focus on occupational and environmental factors.Cohort participantsCONSTANCES was designed as a randomly selected sample of French adults aged 18–69 years at inception; 200 000 participants will be included.Data collection phasesAt enrolment, the participants are invited to complete questionnaires and to attend a health screening centre (HSC) for a health examination. A biobank will be set up. The follow-up includes an yearly self-administered questionnaire, a periodic visit to an HSC and linkage to social and national health administrative databases.Main types of data collectedData collected for participants include social and demographic characteristics, socioeconomic status, life events and behaviours. Regarding occupational and environmental factors, a wealth of data on organisational, chemical, biological, biomechanical and psychosocial lifelong exposure, as well as residential characteristics, are collected at enrolment and during follow-up. The health data cover a wide spectrum: self-reported health scales, reported prevalent and incident diseases, long-term chronic diseases and hospitalisations, sick-leaves, handicaps, limitations, disabilities and injuries, healthcare usage and services provided, and causes of death.Control of selection effectsTo take into account non-participation and attrition, a random cohort of non-participants was set up and will be followed through the same national databases as participants.Data accessInclusions begun at the end of 2012 and more than 110 000 participants were already included by September 2016. Several projects on occupational and environmental risks already applied to a public call for nested research projects.

These results should be taken into account to adapt strategies of mental health disorders prevention at work, for a better efficacy.

The associations between atypical jobs and depressive symptoms differ for job status according to sex and do not seem to be associated with the worst psychosocial working conditions. The interpretation of these results is nonetheless limited in part by the cross-sectional nature of the survey.

The French version of the DCS was found to give a reliable overall score. However, special care should be taken when using the individual subscores. In addition, it is necessary to take into account the context in which the decision-making occurs.