Cohort of people attending health screening centres

Summary

CONSTANCES has several strengths. It was designed both to help answer research questions in diverse areas and to provide public health information needed by the health authorities. The sample will be large, including persons living and working in diverse settings, from large cities to small villages in different regions of France, with a broad range of socioeconomic statuses and trades, allowing for the study of specific economic and professional categories with a satisfactory power for many analyses. The follow-up will be very extensive, relying both on active participation of the volunteers through annual questionnaires and regular medical visits, and on passive methods through regular linkage to health and socioeconomic national exhaustive databases. Numerous data will be collected, including a comprehensive medical, physiological and biological examination and a large biobank. CONSTANCES collects very detailed data on personal, lifestyle, environmental, behavioural, occupational and social factors using state-of-the-art methods. A unique feature of CONSTANCES is also its inclusion of a comprehensive set of cognitive and physical tests starting as young as 45 years, which is earlier in the life-course than most available studies on aging. Of particular importance is the high frequency of measurements from many different sources, allowing for analyses of life-course trajectories of health in relation to personal, social, occupational factors and major life events. Finally, the application comes from an experienced team that has more than 20 years of expertise in successfully designing, implementing and maintaining GAZEL, a large population-based prospective cohort, and in developing numerous fruitful collaborations with French and international groups. The project also has some limitations. Due to the voluntary participation of cohort members, there will probably be an underrepresentation of hard-to-reach subjects, such as heavy drinkers or socially excluded persons. Comparisons between participants and non-participants at inclusion and during the follow-up through regular surveys of non-participants and the randomly selected “non-participants cohort” should allow assessment of potential biases due to selection effects.

Type of data

Data Source
Survey

Type of Study
Cohort study

Data gathering method
Self administered questionnaire
Other: periodic health examination + blood & urine sample + linkage with national databases, see below

Access to data

Conditions of access
downloadable files after agreement.

Type of available data (e.g. anonymised microdata, aggregated tables, etc.)
Anonymised individual data

Formats available
Unknown at the moment, but several usual formats should be available.

Coverage

Coverage Years of collection, reference years, and sample sizes
The CONSTANCES cohort will be a large sample of 200,000 individuals aged 18-69 at inception, included over a five-year period (2012-2016). The duration of follow-up will be as long as possible. Three kinds of data will be collected: annual self-administered questionnaire, medical visit (at inclusion and every 5 years) and regular linkage with SNIIR-AM, CNAV and CépiDC national databases (see below for a description of these databases).

First year of collection
The first participants have been recruited in 2012 (approximately 20,000 during this first year).

Stratification if applicable

Base used for sampling

Geographical coverage and breakdowns
The geographical coverage is incomplete: only 16 districts out of 96 are participating. Nevertheless, the structure of the population for these 16 districts is essentially identical to that of France as a whole for the principal demographic, social, and occupational characteristics.

Age range
Population aged 18-69 at inception.

Statistical representativeness
Population representative

Coverage of main and cross-cutting topics
Data collected will allow for a detailed study of health, wellbeing (medical examination & biological specimens, scales measuring cognitive and physical functioning, including ability to use new technologies, and a specific scale measuring quality of life for senior citizens) and occupational issues (job history; postural, mechanical and organizational constraints; stress at work…). Standard social and demographic characteristics will be collected: social position, educational and income level, employment and marital status, household composition, socioeconomic status of parents and spouse, and material living conditions (type of housing, household income…), including geocoding of the residency address. If necessary, additional information can be collected when needed for nested projects (either on the whole cohort or on subsets of subjects), but these projects will have to pay corresponding additional costs.

Linkage

Standardisation
Whenever it was possible and pertinent scales already published in the literature were used, for which the psychometric properties are already established.

Possibility of linkage among databases
In addition to the data collected through self-administered questionnaires and medical visits, social & work-related events and health data will be followed up by regular linkage with the following national databases: CNAV database (periods of employment and unemployment, sick leave, maternity leave, various social benefits…), SNIIR-AM (it contains reimbursement data for health professionals visits and prescribed drugs, long-term diseases, hospital discharge records…), CépiDc (for vital status and cause of death).

Data quality

Entry errors if applicable

Breaks

Consistency of terminology or coding used during collection
Currently optimal.

Governance

Contact information
Marie Zins, Marcel Goldberg, Lisa Berkman
INSERM / Unité 1018; Plate-forme de recherche « Cohortes en Population »; Hôpital Paul Brousse, Bâtiment 15/16
16, avenue Paul Vaillant Couturier
94807 Villejuif Cedex France Phone: (+33) 01 77 74 74 28 (Marie Zins)
Email: marie.zins(at)inserm.fr
Url: www.constances.fr

Timeliness, transparency
Results will be displayed on a yearly basis (including standard indicators for public authorities, annual reports and a scientific symposium for ancillary nested projects).