[1] NKUA Med Sch, Joint Rheumatol Program, Athens, Greece
[2] St Pauls Hosp, Dept Rheumatol, Thessaloniki, Greece
[3] Metropolitan Hosp, Athens, Greece
[4] Univ Patras, Dept Rheumatol, Patras, Greece
[5] Aristotle Univ Thessaloniki, Dept Internal Med 4, Thessaloniki, Greece
[6] Evangelismos Med Ctr, Rheumatol Clin, Athens, Greece
[7] Thessaly Univ, Dept Rheumatol, Larisa, Greece
[8] Asklepion Hosp, Rheumatol Clin, Athens, Greece
[9] Aristotle Univ Thessaloniki, Rheumatol Sect, Dept Internal Med 1, Thessaloniki, Greece
[10] Univ Crete, Dept Rheumatol Clin Immunol & Allergy, Iraklion, Greece
[11] 251 Air Force Gen Hosp, Dept Rheumatol, Athens, Greece
[12] KAT Gen Hosp, Dept Rheumatol, Athens, Greece
[13] Univ Ioannina, Rheumatol Clin, Ioannina, Greece