1. Department of Neurosurgery, St Olavs University Hospital, Trondheim, Norway
2. Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
3. National Advisory Unit on Spinal Surgery, St Olavs University Hospital, Trondheim, Norway
4. Department of Endocrinology, St Olavs University Hospital, Trondheim, Norway
5. Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
6. Department of Neurosurgery, Haukeland University Hospital, Bergen, Norway
7. Department of Clinical Medicine, University of Bergen, Bergen, Norway
8. Department of Orthopedics, Innlandet Hospital Trust, Lillehammer, Norway
9. Oslo Metropolitan University, Oslo, Norway
10. Department of Neurology, St Olavs University Hospital, Trondheim, Norway
11. Department of Rheumatology, St Olavs University Hospital, Trondheim, Norway
12. Office of Medical Education, Norwegian University of Science and Technology, Trondheim, Norway
13. Department of Public Health and Nursing, Norwegian University of Science and Technology, Trondheim, Norway
14. Department of Neurosurgery, Sahlgrenska University Hospital, Gothenburg, Sweden
15. Department of Neurosurgery, University Hospital of North Norway, Tromsø
16. Department of Clinical Medicine, University of Tromsø, Tromsø, Norway