Table 1.

Variables and data statistics.

Continuous Variables	Mean	Standard Deviation	Min	Max
Health status	0.211	0.144	0	1
Family socioeconomic status	0.189	0.197	0	1
Age	83.872	11.488	60	117
Number of surviving children	3.437	1.786	0	11
Categorial Variables	Categories	n	Percentages (%)	Average Frailty Index
Gender	Female	4228	55.6	0.236
	Male	3371	44.4	0.181
Marital status	Without spouse	4519	59.5	0.252
	With spouse	3080	40.5	0.152
Residential area	Rural	3266	43.0	0.205
	Urban	4333	57.0	0.216
Living with family members	No	1623	21.4	0.214
	Yes	5976	78.6	0.210
Living in an institution	No	7326	96.4	0.207
	Yes	273	3.6	0.320
Old-age insurance	Do not have	3807	50.1	0.219
	Have	3792	49.9	0.203
Medical insurance	Do not have	1049	13.8	0.235
	Have	6550	86.2	0.207
Overall living status	Bad	2645	34.8	0.250
	Good	4954	65.2	0.191
Leisure and recreation status	Bad	7011	92.3	0.220
	Good	588	7.7	0.112
Health-care status	Bad	2438	32.1	0.261
	Good	5161	67.9	0.188