1. Department of Dermatology and Venereology, University Hospital Cologne
2. Institute of Medical Statistics and Computational Biology, Faculty of Medicine, University of Cologne, Cologne
3. Department of Rheumatology and Clinical Immunology, Charité - University Medicine Berlin and Berlin Institute of Health (BIH), Berlin
4. Department of Rheumatology, Justus Liebig University Giessen, Kerckhoff Clinic, Bad Nauheim
5. Department of Rheumatology, University Medical Center-UKSH, Luebeck
6. Department of Dermatology, University Hospital Carl Gustav Carus, Dresden
7. Department for Internal Medicine, Rheumatology, Immunology and Nephrology, Asklepios Clinic Altona, Hamburg
8. Centre for Interdisciplinary Clinical Immunology, Rheumatology and Auto-inflammatory Diseases and Department of Internal Medicine II (Oncology, Hematology, Immunology, Rheumatology, Pulmonology), University Hospital Tuebingen, Tuebingen
9. Department of Rheumatology, University Hospital Heidelberg, Heidelberg
10. Department of Rheumatology, Johanniter-Hospital Treuenbrietzen, Treuenbrietzen
11. Department of Dermatology, University Hospital Ulm, Ulm
12. Department of Rheumatology, Immanuel Hospital Berlin-Buch, Berlin
13. Department of Rheumatology, University Hospital Freiburg, Freiburg
14. Department of Dermatology and Venereology, University Hospital Muenster, Muenster
15. Department of Internal Medicine, Rheumatology and Clinical Immunology, University Clinic of Wuerzburg, Wuerzburg
16. Department of Dermatology and Venereology, Ruhr-University-Bochum, Bochum
17. Department of Rheumatology and Immunology, St. Josef Hospital Wuppertal, Wuppertal
18. Department of Dermatology and Venereology, University Hospital Halle, Halle
19. Department of Rheumatology, University Hospital Erlangen, Erlangen
20. Department of Dermatology and Allergology, Charité – University Medicine Berlin, Berlin
21. Department of Dermatology, Venereology and Allergology, Helios St. Elisabeth Hospital Oberhausen, University Witten-Herdecke, Oberhausen, Germany