[1] Hietzing Hosp, Ctr Rheumat Dis, Dept Internal Med 2, Vienna, Austria
[2] Leiden Univ, Med Ctr, Dept Rheumatol, Leiden, Netherlands
[3] Med Univ Vienna, Dept Internal Med 3, Div Rheumatol, A-1090 Vienna, Austria
[4] Univ Med Ctr Utrecht, Dept Rheumatol & Clin Immunol, Utrecht, Netherlands
[5] Univ Crete, Sch Med, Dept Internal Med, Iraklion, Greece
[6] Humboldt Univ, Charite Hosp, Dept Rheumatol & Clin Immunol, Berlin, Germany
[7] Univ Montpellier, Lapeyronie Hosp, Serv Immunorhumatol, F-34059 Montpellier, France
[8] Univ Genoa, Dept Internal Med, Res Lab, Genoa, Italy
[9] Univ Genoa, Dept Internal Med, Acad Clin Unit Rheumatol, Genoa, Italy
[10] Univ Paris 05, Cochin Hosp, Dept Rheumatol B, Paris, France
[11] Univ Leeds, Acad Unit Musculoskeletal Dis, Leeds, W Yorkshire, England
[12] Univ Erlangen Nurnberg, Inst Clin Immunol, Dept Internal Med 3, Erlangen, Germany
[13] Mt Sinai Hosp, Rebecca MacDonald Ctr Arthrit & Autoimmune Dis, Toronto, ON M5G 1X5, Canada
[14] Diakonhjemmet Hosp, Dept Rheumatol, Oslo, Norway
[15] Hosp La Paz, Madrid, Spain
[16] Univ Pavia, Policlin San Matteo, IRCCS, Dept Rheumatol, I-27100 Pavia, Italy
[17] EULAR Standing Comm People Arthrit Rheumatism Eur, Zurich, Switzerland