Cohort Profile: the Work Environment and Health in Denmark study

Why was the cohort set up?Conditions at the workplace, including physical, chemical, biological, and psychosocial exposures, are important determinants of population health [1][2][3].Considering the ethical and practical constraints of conducting randomized controlled trials on potentially hazardous work conditions, and the limitations of cross-sectional and case-control studies regarding causal interpretations, cohort studies are essential for elucidating the relationships between working conditions and health outcomes.Examples for occupational cohort studies with specific job groups and industries are the British Whitehall II study (civil servants) [4], the French GAZEL study (employees with civil servant-like status in an utility firm) [5], the Finnish Public Key Features The Work Environment and Health in Denmark (WEHD) study was established to monitor employees' work environment and health and to analyse the association between working conditions and health.The nationwide scope and comprehensive linkage to national registries are unique, allowing long-term follow-up with minimal attrition. Survey data of employees in Denmark were collected biennially from 2012 to 2018 with continuous follow-up in national registries, yielding three cohorts, with responders 18-64 years old and 53% women: i) N 88 076 responding to at least one survey and followed up in registries;ii) N 15 852 responding in 2012 and followed up in subsequent waves (2014, 2016, 2018, responders to all four waves: N5933, 37.4%) and registries; iii) N 30 070 responding in either 2012 or 2016 and invited to survey follow-up 2 years later (2014 and 2018, respectively, responders: N 22 445, 74.7%) and followed up in registries. The surveys collected data on physical, chemical, biological, and psychosocial working conditions, and self-reported health.The registries provided sociodemographic, labour market, and health data for responders and responders' cohabiting partners, children, and parents.