1. Cabinet Office. Government of Japan. Annual Report on the Aging Society. 2015; Available from: http://www8.cao.go.jp/kourei/whitepaper/index-w.html . Accessed 14 Aug 2017
2. Bloom DE, Chatterji S, Kowal P, Lloyd-Sherlock P, McKee M, Rechel B, et al. Macroeconomic implications of population ageing and selected policy responses. Lancet. 2015;385:649–57.
3. Soja City. Healthy and 10,000 yen cash back. Available from: http://www.city.soja.okayama.jp/kenkouiryou/iryou_fukushi/cashback.html . Accessed 14 Aug 2017.
4. Lawton MP. Assessing the competence of older people. In: Kent DP, Kastenbaum R, Sherwood S, editors. Research planning and action for the elderly: the power and potential of social science. New York: Behavioral Publications; 1972. p. 122–43.
5. Tsubota-Utsugi M, Ito-Sato R, Ohkubo T, Kikuya M, Asayama K, Metoki H, et al. Health behaviors as predictors for declines in higher-level functional capacity in older adults: the Ohasama study. J Am Geriatr Soc. 2011;59:1993–2000.