1. Tsukuba University School of Medicine, Muribushi Okinawa Center for Teaching Hospitals, Urasoe City, Japan
2. Department of Family and Community Medicine, Saint Louis University School of Medicine, Saint Louis, Missouri, USA
3. University of the Ryukyus School of Medicine, Nishihara City, Japan
4. Jikei University School of Medicine, Minato City, Japan
5. General Hospital Minamiseikyo Hospital, Nagoya City, Japan