[1] Arthrit Res Ctr, Rheumatol, Vancouver, BC, Canada
[2] Univ British Columbia, Expt Med, Vancouver, BC V5Z 1M9, Canada
[3] Arthrit Res Canada, Richmond, BC, Canada
[4] Harvard Univ, Massachusetts Gen Hosp, Sch Med, Rheumatol Allergy & Immunol, Boston, MA USA
[5] Arthrit Res Canada, Rheumatol, Richmond, BC, Canada
[6] Univ British Columbia, Dept Med, Div Rheumatol, Med, Vancouver, BC, Canada