[1] German Rheumatism Res Ctr Berlin, Epidemiol Unit, Berlin, Germany
[2] St Augustin GmbH, Dept Pediat, Asklepios Clin, St Augustin, Germany
[3] Univ Hosp Cologne, Dept Pediat & Adolescent Med, Cologne, Germany
[4] Heinrich Heine Univ Dusseldorf, Hiller Res Ctr, Dusseldorf, Germany
[5] Heinrich Heine Univ Dusseldorf, Dept Rheumatol, Dusseldorf, Germany
[6] Immanuel Krankenhaus Berlin, Dept Internal Med Rheumatol Clin Immunol & Osteol, Berlin, Germany
[7] Rheumatol Schwerpunktpraxis, Berlin, Germany
[8] Rheumatol Struenseehaus, Hamburg, Germany
[9] Charite Univ Med Berlin, Dept Rheumatol & Clin Immunol, Berlin, Germany
[10] Charite Univ Med Berlin, Inst Social Med Epidemiol & Hlth Econ, Berlin, Germany
[11] Free Univ Berlin, Berlin, Germany
[12] Humboldt Univ, Berlin, Germany
[13] Berlin Inst Hlth, Berlin, Germany