1. Leeds Institute of Rheumatic and Musculoskeletal Medicine and University of Leeds; Leeds UK
2. University of California at San Diego
3. Swedish Medical Center and University of Washington School of Medicine; Seattle, Washington
4. Hospital Italiano de Buenos Aires; Buenos Aires Argentina
5. University of Southern California, Keck School of Medicine; Los Angeles
6. Hospital Militar Central and Universidad Militar Nueva Grenada; Bogotá Colombia
7. Geneva University Hospital; Geneva Switzerland
8. Toronto Western Hospital; Toronto Ontario Canada
9. University of Cagliari, Monserrato Campus; Cagliari Italy
10. Louisiana State University Health Sciences Center; New Orleans
11. St. Vincent's University Hospital, The Conway Institute for Biomolecular Research, and University College Dublin; Dublin Ireland
12. University of Toronto and Toronto Western Research Institute; Toronto Ontario Canada
13. Tufts Medical Center; Boston Massachusetts
14. Leeds Institute of Rheumatic and Musculoskeletal Medicine and University of Leeds, Leeds, UK, and Bradford Hospitals NHS Foundation Trust; Bradford UK
15. Cleveland Clinic Foundation; Cleveland Ohio
16. University of Iceland and Landspitali University Hospital; Reykjavik Iceland
17. University of Molise; Campobasso Italy
18. Royal National Hospital for Rheumatic Diseases; Bath UK
19. University of Queensland; Brisbane Queensland Australia
20. University of Pennsylvania; Philadelphia
21. Johns Hopkins University School of Medicine; Baltimore Maryland
22. Chapel Allerton Hospital; Leeds UK
23. St. Vincent's University Hospital; Dublin Ireland
24. Toronto Western Hospital and University of Toronto; Toronto Ontario Canada
25. Hospital for Special Surgery; New York New York
26. Arthritis and Rheumatism Associates; Rockville Maryland
27. Ministry of Health; San Fernando del Valle de Catamarca Argentina
28. University of California; Davis
29. University of Rochester Medical Center; Rochester New York