1. aDivision of Emergency and Transport Services
2. bDepartments of Health Policy
3. cDepartment of Pediatric Surgery, Shizuoka Children’s Hospital, Shizuoka, Japan; and
4. dSchool of Public Health, Department of Medicine, the University of Tokyo, Tokyo, Japan
5. eGeneral Medicine and Interdisciplinary Medicine, National Center for Child Health and Development, Tokyo, Japan