1Institute for Global Health Policy Research, Bureau of International Health Cooperation, National Center for Global Health and Medicine, Shinjuku City, Japan
2Research Center for Financial Gerontology, Keio University, Minato City, Japan
3Research Team for Social Participation and Healthy Aging, Tokyo Metropolitan Institute for Geriatrics and Gerontology, Itabashi City, Tokyo, Japan
4Department of Preventive Medicine and Public Health, Keio University School of Medicine, Shinjuku City, Japan
5Clinical Epidemiology and Biostatistics, School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
6World Health Organization Centre for Health Development, Kobe City, Japan
7Hirao School of Management, Konan University, Nishinomiya City, Japan
8Faculty of Economics, Keio University, Minato City, Japan
9Tokyo Kasei Gakuin University, Chiyoda City, Japan