[1] Leiden Univ, Med Ctr, Dept Rheumatol, NL-2300 RC Leiden, Netherlands
[2] Vrije Univ Amsterdam Med Ctr, Dept Rheumatol, Amsterdam, Netherlands
[3] Haga Hosp, Dept Rheumatol, The Hague, Netherlands
[4] Med Ctr Haaglanden, Dept Rheumatol, The Hague, Netherlands
[5] Med Ctr Rijnmond Zuid, Dept Rheumatol, Rotterdam, Netherlands
[6] Slotervaart Hosp, Dept Rheumatol, Amsterdam, Netherlands
[7] Jan van Breemen Inst, Dept Rheumatol, Amsterdam, Netherlands