1. Rheumazentrum Ruhrgebiet, Claudiusstr 45, Bochum 44649, Herne, Germany
2. Ruhr-Universität Bochum, Bochum, Germany and Rheumazentrum Ruhrgebiet, Herne, Germany
3. Rheumatologische Schwerpunktpraxis, Berlin, Germany
4. Rheumatology Section, Division of Rheumatology, Department of Internal Medicine, University Hospital Leipzig AöR, Clinic and Polyclinic for Gastroenterology and Rheumatology, Leipzig, Germany
5. Medical Franchise Immunology, Novartis Pharma GmbH, Nürnberg, Germany
6. Biostatistics Department, Novartis Pharma GmbH, Nürnberg, Germany
7. Rheumatologisches Versorgungszentrum RVZ Steglitz Berlin, Germany