1. Department of Anaesthesia and Intensive Care Aalborg University Hospital Aalborg Denmark
2. Department of Clinical Medicine Aalborg University Aalborg Denmark
3. Departments of Neurology and Neurosurgery Aalborg University Hospital Aalborg Denmark
4. Department of Respiratory Medicine Aalborg University Hospital Aalborg Denmark
5. Section of Respiratory Medicine Department of Medicine Herlev and Gentofte Hospital University of Copenhagen Hellerup Denmark
6. Department of Anaesthesiology Zealand University Hospital Køge Denmark
7. Department of Anaesthesia and Intensive Care Kolding Hospital University of Southern Denmark Kolding Denmark
8. Department of Public Health Section of Biostatistics University of Copenhagen Copenhagen Denmark
9. Department of Intensive Care Rigshospitalet Copenhagen Denmark