1. Public Health, Department of Social Medicine Osaka University Graduate School of Medicine Osaka Japan
2. Department of Public Health, Faculty of Medicine Beni‐Suef University Beni‐Suef Egypt
3. Department of Public Health, Faculty of Medicine Minia University El‐Minia Egypt
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 National Center for Geriatrics and Gerontology Aichi Japan