1. Department of International and Community Oral Health, Tohoku University Graduate School of Dentistry, Sendai, Japan
2. Division of Statistics and Data Science, Liaison Center for Innovative Dentistry, Graduate School of Dentistry, Tohoku University, Sendai, Japan
3. Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan
4. Department of Social Preventive Medical Sciences, Center for Preventive Medical Sciences, Chiba University, Chiba, Japan
5. Department of Gerontological Evaluation, Center for Gerontology and Social Science, Research Institute, National Center for Geriatrics and Gerontology, Obu, Japan