[1] Nara Med Univ, Dept Publ Hlth Hlth Management & Policy, Sch Med, Nara, Japan
[2] Emergency Life Saving Tech Acad Tokyo, Fdn Ambulance Serv Dev, Tokyo, Japan
[3] Tokyo Univ Hosp, Dept Planning Informat & Management, Tokyo 113, Japan
[4] Univ Tokyo, Grad Sch Med, Dept Hlth Management & Policy, Tokyo, Japan