[1] Univ Munich, Dept Phys Med & Rehabil, D-81377 Munich, Germany
[2] Univ Munich, IMBK, WHO FIC Collaborating Ctr DIMDI, ICF Res Branch, D-81377 Munich, Germany
[3] Univ Zurich, Dept Rheumatol, CH-8006 Zurich, Switzerland
[4] Univ Zurich, Inst Med Phys, CH-8006 Zurich, Switzerland
[5] Univ Hosp, Dept Phys Med & Rehabil, Vienna, Austria
[6] Kaiser Fund Josef Spital, Vienna, Austria