[1] McMaster Univ, Med Sci PhD Grad Program, Hamilton, ON L8S 4L8, Canada
[2] McMaster Univ, Dept Psychiat & Behav Neurosci, Hamilton, ON L8S 4L8, Canada
[3] Hosp Sick Children, Dept Anaesthesia & Pain Med, Toronto, ON M5G 1X8, Canada
[4] Hosp Sick Children, Dept Child Hlth Evaluat Sci, Toronto, ON M5G 1X8, Canada
[5] Univ Toronto, Lawrence S Bloomberg Fac Nursing, Toronto, ON, Canada
[6] Univ Toronto, Dept Anaesthesia, Toronto, ON, Canada