1. World Population Ageing 2019,2019
2. WHO. Ageing and Health 2018. https://www.who.int/news-room/fact-sheets/detail/ageing-and-health/; 2018 Accessed 1 June 2020.
3. Korean Statistical Information Service. National statistics 2018. http://kosis.kr/statisticsList/statisticsListIndex.do?menuId=M_01_01&vwcd=MT_ZTITLE&parmTabId=M_01_01#SelectStatsBoxDiv/; 2020 Accessed 1 June 2020.
4. Quality of life of the elderly residents;Farzianpour;Am J Appl Sci,2012
5. A community-based study of quality of life and depression among older adults;Cao;Int J Environ Res Public Health,2016