From the ∗Center for Injury Research and Prevention
†Division of Emergency Medicine, Children's Hospital of Philadelphia, Philadelphia, PA
‡National Center for Injury Prevention and Control, Centers for Disease Control and Prevention, Atlanta, GA
§Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
∥Sports Medicine and Performance Center, Children's Hospital of Philadelphia, Philadelphia, PA.
Disclosure: The authors declare no conflict of interest.
The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
Reprints: Kristy B. Arbogast, PhD, Center for Injury Research and Prevention, The Children's Hospital of Philadelphia, Roberts Center for Pediatric Research, 2716 South St, 13th Flr, Philadelphia, PA 19146 (e-mail: [email protected]).
This research was supported by an intergovernmental personnel act agreement (14IPA1405502, 15IPA1505513, 14IPA1405503, 14IPA1405504) between the US Department of Health and Human Services (HHS) Centers for Disease Control and Prevention (CDC) and Children's Hospital of Philadelphia.