[1] Med Univ Graz, Klin Abt Rheumatol, Graz, Austria
[2] Mayo Clin, Div Rheumatol, Dept Internal Med, Coll Med, Rochester, MN USA
[3] Mayo Clin, Div Epidemiol, Dept Internal Med, Coll Med, Rochester, MN USA
[4] Mayo Clin, Div Rheumatol, Dept Hlth Sci Res, Coll Med, Rochester, MN USA
[5] Mayo Clin, Div Epidemiol, Dept Hlth Sci Res, Coll Med, Rochester, MN USA
[6] Charite, Med Klin Schwerpunkt Rheumatol & Klin Immunol, Charitepl 1, D-10117 Berlin, Germany