1. Staff Anaesthesiologist.
2. Senior Researcher, National Institute of Occupational Health, Copenhagen, Denmark.
3. Senior Researcher, National Institute of Occupational Health; Department of Employment and Integration, The Danish National Center for Social Research, Copenhagen, Denmark.
4. Senior Registrar, Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark. # See appendix.
5. Consultant, Department of Anesthesia, Center of Head and Orthopedics, Copenhagen University Hospital, Rigshospitalet.