[1] Univ Washington, Dept Anesthesiol & Pain Med, Seattle, WA USA
[2] Seattle Childrens Res Inst, Ctr Child Hlth Behav & Dev, Seattle, WA USA
[3] Hosp Sick Children, Child Hlth Evaluat Sci, Toronto, ON, Canada
[4] Univ Toronto, Inst Hlth Policy Management & Evaluat, Toronto, ON, Canada
[5] Univ Washington, Dept Pediat, Seattle, WA USA
[6] Emory Univ, Dept Pediat, Div Pediat Hematol Oncol Blood & Marrow Transplant, Sch Med, Atlanta, GA USA
[7] Childrens Healthcare Atlanta, Aflac Canc & Blood Disorders, Atlanta, GA USA
[8] Univ Connecticut, Connecticut Childrens Med Ctr, Dept Pediat, Div Pain & Palliat Med,Sch Med, Hartford, CT USA
[9] Northwestern Univ, Feinberg Sch Med, Dept Pediat, Chicago, IL USA
[10] Lurie Childrens Hosp Chicago, Div Hematol Oncol & Stem Cell Transplant, Chicago, IL USA
[11] Univ Toronto, Lawrence S Bloomberg Fac Nursing, Toronto, ON, Canada
[12] Seattle Childrens Res Inst, POB 5371,M-S BC-3, Seattle, WA 98145 USA