1. Division of Community Health; Tohoku University Graduate School of Medicine; Sendai Miyagi Japan
2. Division of Cancer Epidemiology and Prevention; Miyagi Cancer Center Research Institute; Natori Miyagi Japan
3. Center for Preventive Medicine, Osaki Citizen Hospital, Furukawa; Osaki Miyagi Japan
4. Department of Gastroenterology; Miyagi Cancer Center Hospital; Natori Miyagi Japan
5. Department of Surgery; Miyagi Cancer Center Hospital; Natori Miyagi Japan
6. Department of Epidemiology and Public Health; Kanazawa Medical University; Kahoku Ishikawa Japan