[1] HUMANIS Klinikum Lower Austria, Austrian Ctr Rheumatol, Stockerau, Austria
[2] Kaiser Franz Josef Spital, Dept Med 2, Vienna, Austria
[3] Graz Univ, Dept Rheumatol, Graz, Austria
[4] Univ Innsbruck, Rheumatol Unit, A-6020 Innsbruck, Austria
[5] Wels Hosp, Dept Med 2, Wels, Austria
[6] Vienna City Council, Vienna, Austria
[7] Ludwig Boltzmann Inst, Epidemiol Res Unit, Baden, Switzerland
[8] Klagenfurt Hosp, Dept Med 1, Klagenfurt, Austria
[9] Linz Gen Hosp, Dept Med 2, Linz, Austria
[10] Med Univ Vienna, Dept Rheumatol, Vienna, Austria