Objective Danish departments of occupational medicine currently receive about 9,000 patients each year referred due to suspected work-related disorders. In Denmark and internationally there is a lack of follow-up studies investigating the long-term prognosis of employees with work-related disorders. The purpose of this cohort is to facilitate long-term prognostic studies.

Methods The cohort was created through The Danish National Patient Register and comprises all patients seen in Danish Departments/units of Occupational Medicine from 2000–2018 (N= 145,390). Numerous register data are included in the database from five years prior to time of inclusion until 2018. Examples of register data are; information on work, sickness absence and disability as well as number and type of contacts to health services, hospital admissions, income, education, type of occupation, social status, death and cause of death. Job Exposure Matrices (JEMs) on physical and psychosocial work exposure, life styles and other matrices are also available. The cohort will be updated with new patients regularly.

Results Currently the cohort comprises seven major groups: musculoskeletal (n=51.056), mental health (n=28.212), lung (N=12.274), skin (N=6.544), nervous system (N=5.513), cancer (N=1.566), and others (n=40.225). Preliminary analyses across groups suggest that the labor market attachment has been high among the majority (about 75%) of patients during the years prior to the year of inclusion. However, results indicate that the main diagnostic groups, with the exception of skin patients, do not return to comparable levels of labor market attachment during the years following referral and diagnosis.

Conclusions The Danish Occupational Medicine Cohort is an open source dataset available to researchers interested in long-term follow-up on patients with work-related disorders. Preliminary analyses indicate most diagnostic groups do not return to prior levels of labor market attachment during the years following referral and diagnosis from a department of occupational medicine.