[1] Womens Coll Hosp, Rheumatol, Toronto, ON, Canada
[2] Univ Toronto, Med, Toronto, ON, Canada
[3] Univ Toronto, Biochem, Toronto, ON, Canada
[4] Univ Ottawa, Cochrane Musculoskeletal, Ottawa, ON, Canada
[5] Univ Ottawa, Cochrane Equity Methods Grp, Ottawa, ON, Canada
[6] Stanford Univ, Med, Stanford, CA 94305 USA
[7] Univ Washington, Med, Seattle, WA 98195 USA
[8] Swedish Med Ctr, Rheumatol, Seattle, WA USA
[9] Univ Toronto Hlth & Soc, Toronto, ON, Canada