[1] Li X, Fan L, Leng SX. The aging tsunami and senior healthcare development in China. J Am Geriatr Soc 2018;66(8):1462 − 8. https://doi.org/10.1111/jgs.15424CrossRef
[2] Beard JR, Officer A, de Carvalho IA, Sadana R, Pot AM, Michel JP, et al. The World report on ageing and health: a policy framework for healthy ageing. Lancet 2016;387(10033):2145 − 54. https://doi.org/10.1016/S0140-6736(15)00516-4CrossRef
[3] World Health Organization. World report on ageing and health. Geneva: World Health Organization; 2015. https://iris.who.int/handle/10665/186463.
[4] Storeng SH, Sund ER, Krokstad S. Factors associated with basic and instrumental activities of daily living in elderly participants of a population-based survey: the Nord-Trondelag Health Study, Norway. BMJ Open 2018;8(3):e018942. https://doi.org/10.1136/bmjopen-2017-018942CrossRef
[5] Spector WD, Katz S, Murphy JB, Fulton JP. The hierarchical relationship between activities of daily living and instrumental activities of daily living. J Chronic Dis 1987;40(6):481 − 9. https://doi.org/10.1016/0021-9681(87)90004-xCrossRef
[6] Gosling SD, Rentfrow PJ, Swann Jr WB. A very brief measure of the Big-Five personality domains. J Res Pers 2003;37(6):504 − 28. https://doi.org/10.1016/S0092-6566(03)00046-1CrossRef
[7] Li JD. Psychometric properties of ten-item personality inventory in China. China J Health Psychol 2013;21(11):1688 − 92. https://doi.org/10.13342/j.cnki.cjhp.2013.11.008CrossRef
[8] Wong PTP, Reker GT, Gesser G. Death attitude profile—revised: a multidimensional measure of attitudes toward death. In: Neimeyer RA, editor. Death anxiety handbook: research, instrumentation, and application. Washington: Taylor & Francis. 1994; p. 121-148. https://psycnet.apa.org/record/1994-97098-006.
[9] Smith BW, Dalen J, Wiggins K, Tooley E, Christopher P, Bernard J. The brief resilience scale: assessing the ability to bounce back. Int J Behav Med 2008;15(3):194 − 200. https://doi.org/10.1080/10705500802222972CrossRef
[10] Lawton MP. The philadelphia geriatric center morale scale: a revision. J Gerontol 1975;30(1):85 − 9. https://doi.org/10.1093/geronj/30.1.85CrossRef
[11] Inglehart R, Haerpfer C, Moreno A, Welzel C, Kizilova K, Diez-Medrano J, et al. World Values survey: round six - country-pooled datafile version. Madrid: JD Systems Institute. 2014. https://www.worldvaluessurvey.org/WVSDocumentationWV6.jsp.
[12] Li J, Wu ZY, Han BX. Development of mental health inventory for the elderly(urban version). Chin Ment Health J 2009;23(9):656-60. http://www.irgrid.ac.cn/handle/1471x/1665301. (In Chinese). 
[13] Lovibond PF, Lovibond SH. The structure of negative emotional states: comparison of the Depression Anxiety Stress Scales (DASS) with the Beck depression and anxiety inventories. Behav Res Ther 1995;33(3):335 − 43. https://doi.org/10.1016/0005-7967(94)00075-UCrossRef
[14] Lehallier B, Gate D, Schaum N, Nanasi T, Lee SE, Yousef H, et al. Undulating changes in human plasma proteome profiles across the lifespan. Nat Med 2019;25(12):1843 − 50. https://doi.org/10.1038/s41591-019-0673-2CrossRef