1. Division of Health Policy and Management, Center for Community Medicine, Jichi Medical University, Tochigi, Japan
2. Division of Public Health Center for Community Medicine, Jichi Medical University, Tochigi, Japan
3. Section of Postgraduate Guidance, School of Medicine, University of Occupational and Environmental Health, Fukuoka, Japan
4. Department of Biomedical Informatics, The University of Tokyo, Tokyo, Japan
5. Health Service Center, Jichi Medical University, Tochigi, Japan