1. Department of Rheumatology and Clinical Immunology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
2. Rheumatology Department, Chu de Brest, University of Brest, INSERM, Brest, France
3. Department of Rheumatology, AP-HP Ambroise Paré Hospital, University of Versailles Saint Quentin en Yvelines, Boulogne-Billancourt, France
4. Institute of Rheumatology, Prague, Czech Republic
5. Rheumatology Department, University Medical Centre, Ljubljana, Slovenia
6. Academic Rheumatology Centre, Università degli Studi di Torino, Turin, Italy
7. Rheumatology Department, Royal Perth Hospital, Perth, WA, Australia
8. Rheumatology Department, Joint and Bone Research Unit, Hospital Universitario Fundación Jiménez Díaz, Universidad Autónoma, Madrid, Spain
9. Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Berlin, Germany
10. Medical Centre for Rheumatology Berlin-Buch, Immanuel Krankenhaus Berlin, Berlin, Germany
11. Centre for Rheumatology and Spinal Diseases, Rigshospitalet, Copenhagen, Denmark
12. Department of Rheumatology, MC Groep Hospitals, Lelystad, The Netherlands