[1] Murdoch Childrens Res Inst, Anaesthesia & Pain Management Res Grp, Parkville, Vic 3052, Australia
[2] Royal Childrens Hosp, Dept Anaesthesia & Pain Management, Parkville, Vic 3052, Australia
[3] Univ Melbourne, Dept Paediat, Melbourne, Vic, Australia
[4] Univ Glasgow, Acad Unit Anaesthesia Pain & Crit Care, Glasgow, Lanark, Scotland
[5] Royal Hosp Sick Children, Dept Anaesthesia, Glasgow G3 8SJ, Lanark, Scotland
[6] Murdoch Childrens Res Inst, Clin Epidemiol & Biostat Unit, Melbourne, Vic, Australia
[7] Univ Med Ctr Utrecht, Wilhelmina Childrens Hosp, Dept Anaesthesia, Utrecht, Netherlands
[8] Ist Giannina Gaslini, Dept Anesthesia, I-16148 Genoa, Italy
[9] Montreal Childrens Hosp, Dept Anaesthesia, Montreal, PQ H3H 1P3, Canada
[10] McGill Univ, Dept Anesthesia, Montreal, PQ, Canada
[11] Royal Childrens Hosp, Dept Neonatal Med, Melbourne, Vic, Australia
[12] Murdoch Childrens Res Inst, Neonatal Res Grp, Melbourne, Vic, Australia
[13] Univ Oxford, Natl Perinatal Epidemiol Unit, Clin Trials Unit, Oxford, England
[14] Osped Papa Giovanni XXIII, Dept Anaesthesia, Bergamo, Italy
[15] Univ Western Australia, Sch Med & Pharmacol, Pharmacol Pharm Anaesthesiol Unit, Perth, WA 6009, Australia
[16] Princess Margaret Hosp Children, Dept Anaesthesia & Pain Management, Perth, WA, Australia
[17] Starship Childrens Hosp, Auckland Dist Hlth Board, Dept Paediat Anaesthesia & Operating Rooms, Auckland, New Zealand
[18] Osped Pediat Vittore Buzzi, Dept Anesthesiol & Paediat Intens Care, Milan, Italy
[19] La Trobe Univ, Dept Psychol & Counselling, Sch Psychol & Publ Hlth, Melbourne, Vic, Australia
[20] Murdoch Childrens Res Inst, Child Neuropsychol, Melbourne, Vic, Australia
[21] Harvard Univ, Sch Med, Boston Childrens Hosp, Dept Anesthesiol Perioperat & Pain Med, Boston, MA USA