[1] German Soc Rheumatol, Berlin, Germany
[2] Ctr Rheumatol, Munich, Germany
[3] Schoen Hosp, Hamburg, Germany
[4] Univ Med Berlin, Schlosspk Clin, Dept Internal Med, Berlin, Germany
[5] Free Univ Berlin, Charite Univ Med Berlin, Dept Rheumatol & Clin Immunol, Berlin, Germany
[6] Humboldt Univ, D-10099 Berlin, Germany
[7] Univ Leipzig, Dept Rheumatol & Gerontol, D-04109 Leipzig, Germany
[8] Klaus Miehlke Hosp, Dept Internal Med & Rheumatol, Wiesbaden, Germany
[9] St Josef Hosp, Ctr Rheumatol Ruhr, Herne, Germany
[10] Goethe Univ Frankfurt, Dept Rheumatol, Frankfurt, Germany
[11] WWU, Munster, Germany
[12] Ctr Rheumatol & Autoimmunol, Hamburg, Germany
[13] German League Rheumatism, Bonn, Germany
[14] Hosp Neuwittelsbach, Munich, Germany
[15] Hosp Neuwittelsbach, Dept Rheumatol, Munich, Germany
[16] Red Cross Hosp, Dept Internal Rheumatol, Bremen, Germany
[17] Immanuel Hosp, Dept Rheumatol, Berlin, Germany
[18] Heidelberg Univ, Dept Med 5, Div Rheumatol, Heidelberg, Germany
[19] Univ Erlangen Nurnberg, Dept Rheumatol, D-91054 Erlangen, Germany
[20] Univ Cologne, Dept Immunol & Rheumatol, D-50931 Cologne, Germany
[21] Univ Dusseldorf, Dept Rheumatol, Dusseldorf, Germany
[22] Kliniken Essen Sud, Dept Rheumatol & Clin Immunol, Essen, Germany
[23] LMU Munchen, Med Klin & Poliklin 4, Div Rheumatol & Clin Immunol, Munich, Germany
[24] Univ Wurzburg, Dept Rheumatol & Clin Immunol, D-97070 Wurzburg, Germany
[25] Evangel Fachkrankenhaus Ratingen, Ratingen, Germany
[26] Univ Giessen, Kerckhoff Klin, Dept Rheumatol & Clin Immunol, Bad Nauheim, Germany