1. Division of Pediatric Emergency Medicine; Children's Hospital of Philadelphia; Philadelphia PA
2. Perelman School of Medicine; University of Pennsylvania; Philadelphia PA
3. Department of Emergency Medicine; Milwaukee WI
4. Medical College of Wisconsin; Milwaukee WI
5. Department of Emergency Medicine; Beth Israel Deaconess Hospital; Boston MA
6. Department of Emergency Medicine; Albert Einstein Health System; Philadelphia PA
7. Departments of Emergency Medicine & Epidemiology; University of Pennsylvania; Philadelphia PA