What is a cohort ?


A cohort is a group of subjects sharing a certain number of characteristics, followed for years or even decades – known as longitudinal follow-up – according to a pre-established protocol. Cohort studies therefore follow large groups of people to assess the effects on their health of the risk factors to which they are exposed.


Your eating habits, your physical activity, your social and family environment, your search for useful information, your use of medical care, your exposure to pollutants in your place of residence and during your daily commute, your psychological state and relationship to chronic stress, the presence of genetic diseases in your family… all these elements can play a role in your state of health !


Cohorts, which are true research infrastructures, are indispensable tools for exploring and identifying the role of these determinants in individual health trajectories. The longitudinal epidemiological analyses they support enable us to grasp time-related phenomena, in particular the exposure-effect sequence. This makes it possible to model the sequence and interactions of factors linked to living conditions (diet, housing, access to healthcare, social networks, etc.), the environment (working conditions, occupational and environmental exposures, etc.) and health status.