[1] Univ Rochester, Med, Rochester, NY USA
[2] Univ Leeds, Leeds Inst Rheumat & Musculoskeletal Med, Leeds, W Yorkshire, England
[3] Univ Calif San Diego, La Jolla, CA 92093 USA
[4] Swedish Med Ctr, Rheumatol Res, Seattle, WA USA
[5] Hosp Italiano Buenos Aires, Rheumatol, Buenos Aires, DF, Argentina
[6] Hosp Italiano Buenos Aires, Internal Med Serv, Rheumatol Unit, Buenos Aires, DF, Argentina
[7] Univ So Calif, Keck Sch Med, Los Angeles, CA 90033 USA
[8] Fac Med HMC UMNG, Dept Rheumatol, Bogota, Colombia
[9] Univ Hosp Geneva, Dept Dermatol, Geneva, Switzerland
[10] Toronto Western Hosp, Toronto, ON M5T 2S8, Canada
[11] Univ Cagliari, Cagliari, Italy
[12] LSU Med Ctr, Med, Rheumatol Sect, New Orleans, LA USA
[13] Univ Coll Dublin, Sch Med & Med Sci, St Vincents Univ Hosp, Dept Rheumatol, Dublin 2, Ireland
[14] Univ Coll Dublin, Conway Inst Biomol & Biomed Res, Dublin 2, Ireland
[15] Toronto Western Hosp, Div Rheumatol, Toronto, ON M5T 2S8, Canada
[16] Univ Toronto, Toronto, ON, Canada
[17] Tufts Med Ctr, Boston, MA USA
[18] Cleveland Clin, Rheumatol Dept A50, Cleveland, OH 44106 USA
[19] Univ Iceland, Fac Med, Reykjavik, Iceland
[20] Univ Hosp, Reykjavik, Iceland
[21] Univ Molise, Cattedra Reumatol, Campobasso, Italy
[22] Royal Natl Hosp Rheumat Dis, Bath BA1 1RL, Avon, England
[23] Univ Queensland, Dept Med, Brisbane, Qld 4000, Australia
[24] Univ Penn, Med Rheumatol Epidemiol & Biostat, Philadelphia, PA 19104 USA
[25] Johns Hopkins Univ, Rheumatol, Baltimore, MD USA
[26] Chapel Allerton Hosp, Leeds, W Yorkshire, England
[27] St Vincents Univ Hosp, Dublin 4, Ireland
[28] Univ Toronto, Toronto Western Hosp, Div Dermatol, Toronto, ON M5T 2S8, Canada
[29] Hosp Special Surg, Rheumatol, New York, NY 10021 USA
[30] Arthrit & Rheumatism Assoc, Wheaton, MD USA
[31] Minist Hlth, Rheumatol, San Fernando Del Valle D, Argentina
[32] Univ Calif Davis, Dept Dermatol, Davis, CA USA
[33] Univ Rochester, Med Ctr, Allergy Immunol & Rheumatololgy Div, Rochester, NY 14642 USA