1. Department of Rheumatology, Institute of Clinical Medicine, University of Tromsø, Tromsø, Norway,
2. Department of Internal Medicine, Medical University of Debrecen, Debrecen, Hungary
3. Department of Rheumatology, Dr Peter Drzaj Hospital, Ljubljana, Slovenia
4. First Department of Internal Medicine, Szent-Gyorgyi Medical University Centre, Szeged, Hungary
5. Department of Pathophysiology, School of Medicine, National University of Athens, Athens, Greece
6. Department of Connective Tissue Diseases, Institute of Rheumatology, Warsaw, Poland
7. Rheumatology Unit, Istituto Ortopedico Gaetano Pini, Milano, Italy
8. Universita degli Studi di Pisa, Dipartimenti di Medicina Interna, Italy
9. Department of Internal Medicine, Faculty of Medicine, University of Tartu, Estonia
10. Department of Internal Medicine and Institute for Clinical Immunology, University of Erlangen-Nurnberg, Erlangen, Germany
11. Medical Clinic, Department of Rheumatology, Heinrich-Heine University, Dusseldorf, Germany
12. Division of Rheumatology, Herlev Hospital, University of Copenhagen, Denmark
13. Department of Rheumatology, Karolinska Institute, Stockholm, Sweden
14. Department of Rheumatology, Ikazia Ziekenhuis, Rotterdam, The Netherlands