Table 4.

Data balance test before and after matching

Variables	Sample	Average value		SD%	t-test
		Treatment group	Control group		t	P >|t|
Gender	Before Matching	0.325	0.525	99.8	-3.23	0.001
	After matching	0.329	0.330		-0.01	0.996
Age	Before Matching	70.117	65.771	94.9	3.85	0.000
	After matching	70.026	69.803		0.16	0.874
living area	Before Matching	0.818	0.779	92.7	0.77	0.444
	After matching	0.816	0.819		-0.05	0.964
Region	Before Matching	0.338	0.357	-158.8	-0.33	0.742
	After matching	0.329	0.380		-0.65	0.515
Ethnic group	Before Matching	0.117	0.075	54.2	1.24	0.216
	After matching	0.105	0.086		0.40	0.687
Education level	Before Matching	0.883	1.062	76.9	-2.08	0.038
	After matching	0.895	0.936		-0.36	0.719
Number of chronic diseases	Before Matching	2.377	2.720	70.7	-1.30	0.194
	After matching	2.408	2.374		0.33	0.745