| Affiliation: | 1. Department of Emergency Medicine, Feinberg School of Medicine, Northwestern University, 211 East Ontario Street, Suite 200, Chicago, IL 60611, USA;2. United States Soccer Federation;1. Department of Emergency Medicine, Pediatric Emergency Medicine, Maine Medical Center, 22 Bramhall Street, Portland, ME 04102, USA;2. Tufts University School of Medicine, Boston, MA, USA;3. Pediatric Emergency Medicine, Maine Medical Center, 22 Bramhall Street, Portland, ME 04102, USA;1. Division of Emergency Medicine, Department of Family and Community Medicine, University of Toronto, Toronto, Canada;2. Department of Emergency Medicine, Mayo Clinic, 200 First Street, Southwest, Rochester, MN 55905, USA;1. Emergency Department, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue C7-53, Toronto, Ontario M4N 3M5, Canada;2. Emergency Department, North York General Hospital, Toronto, Ontario, Canada;1. Emergency Medical Services, United States Air Force, 96TW/SGOE, 307 Boatner Road, Eglin AFB, FL 32542, USA;2. Department of Emergency Medicine, University of Maryland Medical Center, 110 South Paca Street, 6th Floor, Suite 200, Baltimore, MD 21201, USA |
