1. Department of Pediatrics and Critical Care Medicine, Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
2. Department of Pediatrics, Section of Critical Care, Children's Hospital Colorado, Aurora, Colorado, United States
3. Department of Anesthesiology and Critical Care Medicine and Pediatrics, Johns Hopkins University School of Medicine, The Charlotte R. Bloomberg Children's Center, Baltimore, Maryland, United States
4. Department of Psychology and Neuroscience Center, Brigham Young University, Provo, Utah, United States