Table 3.

Covariate balance test after propensity score matching

	Standardized differences		Variance ratio
	Raw	Matched	Raw	Matched
Gender (ref = Male)
Female	−0.1059	−0.0389	0.8552	0.9437
Elderly (ref = No)
Yes	0.6012	−0.0068	1.1173	0.9976
Education level (ref = Middle school or less)
High school or more	−0.2761	0.0378	1.0598	0.9888
Presence of a spouse (ref = No)
Yes	0.0736	0.0476	0.9174	0.9434
Economically active (ref = No)
Yes	−0.5098	0.0203	1.3894	0.9834
Living alone (ref = No)
Yes	−0.0148	0.0061	0.9744	1.0110
Equivalized income (ref = 1st quintile)
2nd quintile	0.1051	−0.0302	1.1395	0.9630
3rd quintile	−0.0029	0.0121	0.9962	1.0183
4th quintile	−0.2189	0.0295	0.6819	1.0491
5th quintile	−0.1585	−0.0187	0.7363	0.9662
Private health insurance (ref = No)
Yes	−0.3315	−0.0078	1.4291	1.0090
National health insurance (ref = No)
Yes	0.1971	−0.0056	2.0315	0.9789
Presence of disabled persons (ref = No)
Yes	0.3362	0.0091	2.1813	1.0230