1. University of Twente Enschede The Netherlands
2. International Consortium for Health Outcomes Measurement London UK
3. University Medical Center Utrecht Utrecht The Netherlands
4. Maastricht University Medical Centre Maastricht The Netherlands
5. Hong Kong Psoriatic Arthritis Association Hong Kong China
6. University Hospitals of Geneva and University of Geneva Geneva Switzerland
7. University of Alabama at Birmingham
8. Imperial College Healthcare NHS Trust London UK
9. Karolinska Institutet Stockholm Sweden
10. Sorbonne Université and Pitié Salpêtrière HospitalAP‐HP Paris France
11. Lockton Dunning Benefits Dallas Texas
12. Columbia University Medical Centre New York New York
13. Singapore General Hospital, Duke‐NUS Medical School Singapore
14. Sheba Medical Centre Tel‐Hashomer Israel
15. Providence St. Joseph Health SystemUniversity of Washington Seattle
16. University of Nebraska Medical Center Omaha, and the National Databank for Rheumatic Diseases Wichita Kansas
17. University of KwaZulu‐Natal Durban South Africa
18. University of the West of England Bristol UK
19. Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil
20. Instituto Universitario Hospital Italiano de Buenos Aires Buenos Aires Argentina
21. University of Otago Wellington New Zealand
22. Maasstad Hospital Rotterdam The Netherlands
23. VU University Medical CentreAmsterdam Public Health Amsterdam The Netherlands
24. Wilhelmina Children’s Hospital Utrecht The Netherlands
25. University of Twente, Enschede, The Netherlands, and International Consortium for Health Outcomes Measurement London UK