1. Department of Epidemiology and Social Medicine University of Aarhus Aarhus
2. Department of Social Medicine County of Aarhus Aarhus
3. Department of Internal Medicine Herning Central Hospital Herning
4. Department of Clinical Epidemiology, Departments of Aarhus University Hospital Aarhus
5. Clinical Microbiology Aalborg Hospital Aalborg
6. Occupational Health Aalborg Hospital Aalborg