1. Department of Dermatovenereology; Haukeland University Hospital; Bergen Norway
2. Department of Clinical and Experimental Medicine; Faculty of Medicine and Health Sciences; Linköping University; Linköping Sweden
3. Skånes Universitetssjukhus; Malmö Sweden
4. Copenhagen Center for Arthritis Research; Center for Rheumatology and Spine Diseases; Rigshospitalet, Glostrup; University of Copenhagen; Copenhagen Denmark
5. Department of Dermatology and Allergy; Herlev and Gentofte Hospital; University of Copenhagen; Copenhagen Denmark
6. UiT The Arctic University of Norway; Tromsø Norway
7. Department of Dermatology; University Hospital of North Norway; Tromsø Norway
8. Department of Dermatology; Aarhus University Hospital; Aarhus Denmark
9. Division of Dermatology; Ryhov Hospital; Jönköping Sweden