1 Department of Pediatrics, Center for Safe and Healthy Families, Primary Children's Hospital, The University of Utah, Salt Lake City.
2 Division of General Pediatrics, Clinical Futures, and PolicyLab, Roberts Center for Pediatric Research, Perelman School of Medicine at the University of Pennsylvania, Philadelphia.
3 Department of Pediatrics, University of Pittsburgh Medical Center Children's Hospital of Pittsburgh, Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, Pennsylvania.