1. Department of Community Health and Preventive Medicine, Hamamatsu University School of Medicine, Hamamatsu City, Japan
2. Faculty of Social Policy & Administration, Hosei University, Machida, Japan
3. Department of Oral Health Promotion, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Japan
4. Department of Ophthalmology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Japan
5. Department of Social Preventive Medical Sciences, Center for Preventive Medical Sciences, Chiba University, Chiba, Japan
6. Department of Gerontological Evaluation, Center for Gerontology and Social Science, National Center for Geriatrics and Gerontology, Obu City, Japan