[1] Univ Toronto, Div Rheumatol, Toronto, ON, Canada
[2] Univ Toronto, Dept Med, Toronto, ON, Canada
[3] Stanford Univ, Sch Med, Div Rheumatol Immunol, Palo Alto, CA 94304 USA
[4] Johns Hopkins Univ, Sch Med, Baltimore, MD USA
[5] Northern Ontario Sch Med, Greater Sudbury, ON, Canada