1. Division of Sports Medicine, Department of Orthopedics, Warren Alpert Medical School, Brown University, Injury Prevention Center, Rhode Island Hospital/Hasbro Children’s Hospital, Providence, Rhode Island;
2. Center for Injury Research and Policy, The Research Institute at Nationwide Children’s Hospital, Columbus, Ohio;
3. Department of Pediatrics, College of Medicine, and
4. Division of Epidemiology, College of Public Health, Ohio State University, Columbus, Ohio;
5. Department of Anesthesia, and
6. Fairfax County Public Schools, Falls Church, Virginia
7. Division of Sports Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts; and