Table 3.

Decomposition Analysis of Concentration Index in ADL Score

Variable	Elasticity	Ck	Absolute Contribution to C	Percentage Contribution to C
Age
60–69	Ref
70–79	0.0119	−0.0938	−0.0011	17.37
≥ 80	0.0065	−0.0717	−0.0005	7.19
Gender
Female	Ref
Male	−0.0088	0.0610	−0.0005	8.38
Marital status
Divorced or else	Ref
Married	0.0049	0.0108	0.0001	−0.81
Educational Attainment
Primary school and below	Ref
Junior high school	−0.0020	0.1455	−0.0003	4.41
Senior high school	−0.0006	0.1790	−0.0001	1.61
Higher education	−0.0001	0.1629	0.00001	0.23
Household income	−0.0202	0.1315	−0.0027	41.15
Health Insurance
Without health insurance	Ref
Covered by health insurance	−0.0132	0.0022	0.00003	0.46
Geographic Location
Living in eastern region	Ref
Living in central region	0.0036	0.0385	0.0001	−2.14
Living in western region	−0.0080	0.0011	0.000009	0.14
Residency Location
Living in rural area	Ref
Living in urban area	−0.0072	0.0514	−0.0004	5.78
Smoking
No	Ref
Yes	−0.0027	0.0226	−0.0001	0.93
Drinking
No	Ref
Yes	−0.0027	0.0530	−0.0001	2.22
Social Interaction
No	Ref
Yes	−0.0152	−0.0050	0.0001	−1.18

Notes: C_k indicates the concentration index of each explanatory variable; C stands for the concentration index of each independent variable; Ref represents the reference group.