[1] Italian Soc Rheumatol SIR, Epidemiol Res Unit, Milan, Italy
[2] Univ Hosp Parma, Internal Med & Rheumatol Unit, Dept Med, Parma, Italy
[3] Ctr Specialist Ortoped Traumatol Gaetano Pini CTO, Rheumatol Clin, Milan, Italy
[4] Azienda Osped Univ Senese, Rheumatol Unit, Siena, Italy
[5] Univ Bari, Rheumatol Unit, Dept Emergency & Organ Transplantat, Bari, Italy
[6] Univ Politecn Marche, Spectate Carlo Urban, Rheumatol Clin, Jesi, AN, Italy
[7] Azienda Osped San Camillo Forlanini, Rheumatol Unit, Rome, Italy
[8] Univ Ferrara, Rheumatol Sect, Dept Med Sci, Ferrara, Italy
[9] Azienda Osped Citta Salute & Sci Torino, Rheumatol Unit, Turin, Italy