[1] Univ Toronto, Dept Phys Therapy, Toronto, ON, Canada
[2] Hosp Sick Children, Dept Rehabil, Toronto, ON, Canada
[3] Hosp Sick Children, Res Inst, Child Hlth Evaluat Sci, Toronto, ON, Canada
[4] Tufts Univ, Dept Child Study & Human Dev, Medford, MA USA
[5] Friedrich Schiller Univ Jena, Dept Clin Psychol, Jena, Germany
[6] Univ Toronto, Lawrence S Bloomberg Fac Nursing, Toronto, ON, Canada
[7] Boston Childrens Hosp, Dept Anesthesiol Crit Care & Pain Med, Boston, MA USA
[8] Harvard Med Sch, Dept Anaesthesia, Boston, MA USA
[9] Harvard Med Sch, Dept Psychiat, Boston, MA USA
[10] Hosp Sick Children, Dept Rehabil & Child Hlth Evaluat Sci, 555 Univ Ave, Toronto, ON M5G1X8, Canada