Cabinet Office. (2013) Annual Report on the Aging Society: 2013 (Summary).
 Ministry of Health, Labour and Welfare. Abridged Life Tables for Japan 2015.
 Demura, S. and Sato, S. (2006) Quality of Life (QOL) Assessment for Japanese Elderly: The Course of QOL Studies and Assessments of Health-Related and Subjective QOL. Japan Journal of Physical Education, Health and Sport Sciences, 51, 103-115.
 Hoshi, T., Takagi, C., Inoue, N., Nakayama, N., Yuasa, M. and Sakurai, N. (2012) Causal Effects of Socio-Economic Variables on the “Three Health Factors” among Elderly Urban Dwellers. Japanese Journal of Health Education and Promotion, 20, 159-170.
 Hatayama, T., Matsuo, E., Murakami, K., Nagano, M., Moriyama, Y. and Kumagai, S. (2012) Quality of Life in Community-Dwelling Elderly: Dazaifu Study. Journal of Health Science, 34, 43-53.
 de Belvis, A.G., Avolio, M., Sicuro, L., Rosano, A., Latini, E., Damiani, G. et al. (2008) Social Relationships and HRQL: A Cross-Sectional Survey among Older Italian Adults. BMC Public Health, 8, 348.
 Li, C.I., Lin, C.H., Lin, W.Y., Liu, C.S., Chang, C.K., Meng, N.H., et al. (2014) Successful Aging Defined by Health-Related Quality of Life and Its Determinants in Community-Dwelling Elders. BMC Public Health, 14, 1013.
 Lim, J.T., Park, J.H., Lee, J.S., Oh, J. and Kim, Y. (2013) The Relationship between the Social Network of Community-Living Elders and Their Health-Related Quality of Life in Korean Province. Journal of Preventative Medicine and Public Health, 46, 28-38.
 Thomé, B., Dykes, A.K. and Hallberg, I.R. (2004) Quality of Life in Old People with and without Cancer. Quality of Life Research, 13, 1067-1080.
 Kempen, G.I., Ormel, J., Brilman, E.I. and Relyveld, J. (1997) Adaptive Responses among Dutch Elderly: The Impact of Eight Chronic Medical Conditions on Health-Related Quality of Life. American Journal of Public Health, 87, 38-44.
 Saito, T., Sakita, M., Matuo, E., Nofuji, Y., Moriyama, Y., Nagano, M., et al. (2012) Effects of Differences in Level of Knee Pain and Affected Side on Mental Health in Elderly. Japanese Journal of Health Promotion and Physical Therapy, 1, 21-28.
 Iwaya, T., Shirakihara, N. and Tobimatsu, Y. (2005) The Effects of Low Back Pain on Physical and Social Function in Elderly People Living in Rural Area. Journal of Japanese Society of Lumbar Spine Disorders, 11, 27-34.
 World Health Organization (1998) Review of the Constitution of the World Health Organization: Report of the Executive Board Special Group.
 Takeda, K., Futoyu, Y., Kirino, M., Kumo, K., Kim, J.S. and Nakajima, K. (2007) Development of a Spirituality Rating Scale Related to Health in the Elderly: A Study of the Validity and Reliability. The Journal of Japan Academy of Health Sciences, 10, 63-72.
 Konopack, J.F. and McAuley, E. (2012) Efficacy-Mediated Effects of Spirituality and Physical Activity on Quality of Life: A Path Analysis. Health and Quality of Life Outcomes, 10, 57.
 Yoon, D.P. and Lee, E.K. (2006) The Impact of Religiousness, Spirituality, and Social Support on Psychological Well-Being among Older Adults in Rural Areas. Journal of Gerontological Social Work, 48, 281-298.
 Parker, L., Moran, G.M., Roberts, L.M., Calvert, M. and McCahon, D. (2014) The Burden of Common Chronic Disease on Health-Related Quality of Life in an Elderly Community-Dwelling Population in the UK. Family Practice, 31, 557-563.
 Kurimoto, A., Awata, S., Ohkubo, T., Tsubota-Utsugi, M., Asayama, K., Takahashi, K., et al. (2011) Reliability and Validity of the Japanese Version of the Abbreviated Lubben Social Network Scale. Japan Geriatrics Society Journal, 48, 149-157.
 Singer, M.A., Hopman, W.M. and Mac Kenzie, T.A. (1999) Physical Functioning and Mental Health in Patients with Chronic Medical Conditions. Quality of Life Research, 8, 687-691.
 Kondo, K., Ashida, T., Hirai, H., Misawa, J. and Suzuki K. (2012) The Relationship between Socio-economic Status and the Loss of Healthy Aging, and Relevant Gender Differences in the Japanese Older Population: AGES Project Longitudinal Study. Journal of Health and Society, 22, 19-30.
 Okano, G., Hattori, M. and Kawai, M. (2012) Relationship between Health Status and a Family Budget in Older People Living in Community. Ryukoku University Research Institute for Social Sciences Yearly Report, 43, 173-181.
 Fujiwara, Y., Kobayashi, E. and Fukaya, T. (2012) Cross-Sectional Relationships between Social Determinants of Health: Annual Income or Subjective Economic Status and Psychological Variables. Japanese Journal of Geriatric Psychiatry, 23, 211-220.