1. Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu, Japan
2. Department of Disaster and Emergency Medicine, Kochi Medical School, Nankoku, Japan
3. Department of Emergency Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
4. Department of Medical Education, Chiba University Hospital, Chiba, Japan
5. Department of Emergency Medicine, Chiba Kaihin Municipal Hospital, Chiba, Japan