[1] Univ Hosp Southern Denmark, Danish Hosp Rheumat Dis, Sonderborg, Denmark
[2] Univ Southern Denmark, Dept Reg Hlth Res, Odense, Denmark
[3] Danish Rheumatism Assoc Rehabil Ctr, Sano, Denmark
[4] Univ Hosp Southern Denmark, Hosp Southern Jutland, Aabenraa, Denmark
[5] Lund Univ, Dept Clin Sci, Sect Rheumatol, Lund, Sweden
[6] Spenshult Res & Dev Ctr, Halmstad, Sweden
[7] Univ Hosp Southern Denmark, Danish Hosp Rheumat Dis, Engelshojgade 9A, DK-6400 Sonderborg, Denmark