1. Department of Medical Informatics, Biometry and Epidemiology, Ruhr University Bochum, Bochum, Germany, and Rheumatology Practice Gladbeck Gladbeck Germany
2. Department of Medical Informatics, Biometry and Epidemiology Ruhr University Bochum Bochum Germany
3. Ruhr Area Rheumatism Centre, Ruhr University Bochum Bochum Germany
4. Rheumatology Practice Hattingen Hattingen Germany
5. Rheumatology Practice Duisburg Duisburg Germany
6. Rheumatology Practice Gladbeck Gladbeck Germany
7. Rheumatology Practice Marl Marl Germany
8. Rheumatology Practice Oberhausen Oberhausen Germany
9. Rheumatology Practice Minden Minden Germany
10. Rheumatology Practice Bochum Bochum Germany
11. Rheumatology Practice Dortmund Dortmund Germany
12. Rheumatology Practice Bielefeld Bielefeld Germany
13. Department of Rheumatology Evangelisches Fachkrankenhaus und Altenhilfe Ratingen gGmbH Ratingen Germany
14. Rheumatology Practice Ratingen Ratingen Germany
15. Centre for Clinical Studies, Institute of Medical Informatics, Biometry and Epidemiology University of Duisburg‐Essen Duisburg Germany
16. University of Applied Sciences Düsseldorf Düsseldorf Germany
17. Centre for Clinical Studies, Philipps University of Marburg Marburg Germany