1. King Christian X’s Hospital for Rheumatic Diseases, Graasten, Denmark
2. Institute for Regional Health Research, University of Southern Denmark, Odense, Denmark
3. Hospital of Southern Jutland, Aabenraa, Denmark
4. Danbio Registry, Rigshospitalet Glostrup, Glostrup, Denmark
5. Musculoskeletal Statistics Unit, The Parker Institute, Bispebjerg and Frederiksberg Hospitals, Copenhagen, Denmark
6. Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet Glostrup, Glostrup, Denmark
7. Faculty of Health Scienses, University of Southern Denmark, Odense, Denmark