[1] Univ Alberta, Med, Edmonton, AB, Canada
[2] Chinese Peoples Liberat Army Gen Hosp, Rheumatol, Beijing 100853, Peoples R China
[3] Mahidol Univ, Siriraj Hosp, Med, Rheumatol, Bangkok 10700, Thailand
[4] Univ Alberta, Radiol, Edmonton, AB, Canada
[5] McGill MUHC RVH, Rheum Clin Epid, Montreal, PQ, Canada
[6] Univ Copenhagen, Glostrup Hosp, Copenhagen Ctr Arthrit Res, Copenhagen, Denmark