[1] Hosp Sick Children, Toronto, ON, Canada
[2] Toronto Western Hosp, Krembil Res Inst, Toronto, ON, Canada
[3] Ann & Robert H Lurie Childrens Hosp Chicago, Chicago, IL 60611 USA
[4] Univ Toronto, Toronto, ON, Canada
[5] Univ Toronto, SickKids Hosp Fac Med, Div Rheumatol, Toronto, ON, Canada
[6] Hosp Special Surg, 535 E 70th St, New York, NY 10021 USA
[7] Univ Manitoba, Winnipeg, MB, Canada
[8] Univ Western Ontario, London, ON, Canada
[9] Univ Hlth Network, Toronto Western Hosp, Div Rheumatol, Ctr Prognosis Studies, Toronto, ON, Canada
[10] Univ Toronto, Inst Hlth Policy Management & Evaluat, Toronto, ON, Canada
[11] Univ Toronto, Krembil Res Inst, Div Geneticsand Dev, Toronto, ON, Canada
[12] Univ Toronto, Univ Hlth Network, Div Rheumatol, Toronto, ON, Canada
[13] Univ Toronto, Dept Immunol, Toronto, ON, Canada
[14] Hosp Sick Children, Div Rheumatol, Toronto, ON, Canada
[15] Univ Toronto, SickKids Res Inst, Div Translat Med & Genet, Toronto, ON, Canada
[16] Univ Toronto, SickKids Res Inst, Div Genet, Toronto, ON, Canada
[17] Univ Toronto, Fac Med, Toronto, ON, Canada