1. Department of Clinical Study and Informatics, Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan
2. Department of Public Health/Health Policy, Graduate School of Medicine, the University of Tokyo, Tokyo, Japan
3. Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA
4. Center for Clinical Epidemiology, St. Luke's International University, Tokyo, Japan
5. Division of General Medicine and Primary Care, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA
6. Harvard Interfaculty Initiative in Health Policy, Cambridge, MA