1. Center of Rheumatology and Spine Diseases, Copenhagen Center for Arthritis Research, Glostrup University Hospital, Glostrup
2. Department of Rheumatology, Diakonhjemmet Hospital, Oslo
3. Department of Rheumatology, Parker Institute, Copenhagen
4. Department of Rheumatology, University of Copenhagen Hospital at Koege
5. Department of Rheumatology, Sapienza Università di Roma, Rome
6. Rheumatology Department, Paris Ouest-Versailles-Saint Quentin en Yvelines University, Paris
7. Medical Centre for Rheumatology, Immanuel Krankenhaus, Berlin
8. Department of Rheumatology, Hospital Universitario de Móstoles, Madrid
9. Department of Rheumatology, MC Groep, Lelystad
10. Department of Rheumatology, Clinica Reumatologica, Università Politecnica delle Marche, Jesi
11. Rheumatology Department, Instituto Poal, Barcelona
12. 3rd Department of Rheumatology, National Institute of Rheumatology and Physiotherapy, Budapest
13. LIMM Section of Musculoskeletal Disease, Chapel Allerton Hospital, Leeds
14. Department of Rheumatology, Hospital General Universitario Gregorio Marañón, Madrid