[1] Univ Hosp, Dept Internal Med, Div Rheumatol, NL-6202 AZ Maastricht, Netherlands
[2] Univ Hosp, Dept Clin Epidemiol & Evaluat, Nancy, France
[3] Univ Maastricht, Dept Methodol & Stat, Maastricht, Netherlands
[4] Erasmus Univ, Inst Med Technol Assessment, Rotterdam, Netherlands
[5] Univ Paris 05, Dept Rheumatol, Paris, France
[6] State Univ Ghent Hosp, Dept Rheumatol, B-9000 Ghent, Belgium
[7] Maasland Ziekenhuis Sittart, Sittard, Netherlands