1 Centre for Child Health, Behavior, Development, Seattle Children's Research Institute, Seattle, WA, USA Departments of Anesthesiology, Pediatrics, and Psychiatry, University of Washington, Seattle, WA, USA Department of Pediatrics, Dalhousie University Department of Psychology and Neuroscience, Dalhousie University Centre for Pediatric Pain Research, IWK Health Centre Clinical, Social and Administrative Pharmacy, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada Child Health Evaluative Sciences, The Hospital for Sick Children Department of Clinical Psychology, Justus-Liebig University, Gießen, Germany.