[1] Hosp Gen Univ Elda, Dept Reumatol, Elda 03600, Spain
[2] Hosp Gen Univ Alicante, Dept Reumatol, Alicante, Spain
[3] Univ Camilo Jose Cela, Fac Ciencias Salud, Madrid, Spain
[4] Univ British Columbia, Div Rheumatol, Vancouver, BC V5Z 1M9, Canada
[5] Royal Melbourne Hosp, Parkville, Vic 3050, Australia
[6] Univ Hosp Southampton NHS Fdn Trust, Southampton, Hants, England
[7] NIHR Wellcome Trust Clin Res Facil, Southampton, Hants, England
[8] Ctr Hosp Univ Liege, Liege, Belgium
[9] Maastricht Univ, Med Ctr, Dept Internal Med Rheumatol, Maastricht, Netherlands
[10] Atrium Med Ctr, Heerlen, Netherlands
[11] Univ Toronto, Div Rheumatol, Toronto, ON, Canada
[12] Repatriat Gen Hosp, Rheumatol Res Unit, Adelaide, SA, Australia
[13] Flinders Univ S Australia, Adelaide, SA 5001, Australia
[14] Med Univ Vienna, Dept Internal Med 3, Div Rheumatol, Vienna, Austria
[15] Univ Toronto, Dept Hlth Policy Management & Evaluat, Toronto, ON, Canada
[16] Mt Sinai Hosp, Univ Hlth Network, Toronto Gen Res Inst, Div Clin Decis Making & Hlth Care, Toronto, ON M5G 1X5, Canada
[17] Cabrini Hosp, Monash Dept Clin Epidemiol, Malvern, Vic, Australia
[18] Monash Univ, Dept Epidemiol & Prevent Med, Malvern, Vic, Australia
[19] Univ Amsterdam, Acad Med Ctr, Dept Clin Immunol & Rheumatol, NL-1105 AZ Amsterdam, Netherlands
[20] Univ Med Ctr Utrecht, Dept Rheumatol & Clin Immunol, Utrecht, Netherlands
[21] Univ Nova Lisboa, Fac Ciencias Med, CEDOC, P-1200 Lisbon, Portugal
[22] EPE Hosp Egas Moniz, CHLO, Dept Rheumatol, Lisbon, Portugal
[23] Hosp Gen Mexico City, Rheumatol Unit, Mexico City, DF, Mexico
[24] Karolinska Univ Hosp, Dept Rheumatol, Stockholm, Sweden
[25] Karolinska Inst, Stockholm, Sweden
[26] Ghent Univ Hosp, Dept Rheumatol, Ghent, Belgium
[27] Univ Fed Sao Paulo, Div Rheumatol, Sao Paulo, Brazil
[28] St Georges Healthcare NHS Trust, Dept Rheumatol, London, England
[29] State Hosp Stockerau, Ctr Rheumatol, Lower Austria, Stockerau, Austria
[30] Univ Pavia, IRCCS Policlin S Matteo, Cattedra Reumatol, I-27100 Pavia, Italy
[31] Univ Giessen, Kerckhoff Klin, Dept Rheumatol & Clin Immunol, Bad Nauheim, Germany
[32] Copenhagen Univ Hosp, Ctr Rheumatol & Spine Dis, Copenhagen Ctr Arthrit Res, Glostrup, Denmark
[33] Menzies Res Inst Tasmania, Hobart, Tas, Australia
[34] Columbia Univ, Med Ctr, New York, NY USA
[35] Leiden Univ, Med Ctr, Leiden, Netherlands