Dental expenditure, progressivity and horizontal inequality in Chinese adults: based on the 4th National Oral Health Epidemiology Survey

Table 2 Decomposition of concentration index for dental expenditure

Variables	Model 1				Model 2
Variables	Elasticities	Concentration indices	Contributions	Percentage of contributions	Elasticities	Concentration indices	Contributions	Percentage of contributions
Household income	0.0716	0.4975	0.0356	18.24%	0.0715	0.4757	0.0340	50.43%
Central region	−0.0838	−0.0565	0.0047	2.42%	−0.0811	−0.0312	0.0025	3.76%
Western region	−0.0166	−0.0884	0.0015	0.75%	−0.0141	−0.1092	0.0015	2.29%
Area-Urban area	−0.2886	−0.0554	0.0160	8.19%	−0.3363	−0.0441	0.0148	22.02%
Education	0.1227	0.1138	0.0140	7.15%	0.1575	0.0919	0.0145	21.48%
UEBMI	0.0109	0.2668	0.0029	1.49%	0.0413	0.1945	0.0080	11.92%
URBMI	−0.0064	0.0520	−0.0003	−0.17%	0.0007	−0.0071	0.0000	−0.01%
NRCMC	0.0036	−0.1825	−0.0007	− 0.34%	0.0215	− 0.2233	−0.0048	−7.12%
Other insurance	0.0162	0.3166	0.0051	2.63%	0.0122	0.2540	0.0031	4.60%
Age	0.3584	−0.0466	−0.0167	−8.56%	0.3578	−0.0373	−0.0133	−19.79%
Gender-Female	0.0707	−0.0125	−0.0009	− 0.45%	0.0904	− 0.0171	−0.0015	−2.30%
Nationality-Han	−0.0056	−0.0688	0.0004	0.20%	−0.0043	−0.2011	0.0009	1.27%
Teeth brushing habit-twice daily	0.0941	0.1494	0.0141	7.20%	0.1053	0.0995	0.0105	15.53%
Self-reported oral health	0.3398	−0.0176	−0.0060	−3.06%	0.4806	−0.0187	−0.0090	−13.32%
DT	−0.0062	−0.1036	0.0006	0.33%	−0.0002	−0.0914	0.0000	0.03%
Dental utilization	0.9682	0.1216	0.1177	60.28%	–	–	–	–
Residual			0.0072	3.70%			0.0062	9.22%
Total			0.1952	100.00%			0.0674	100.00%

Legend: Model 1 enrolled all participants and Model 2 enrolled those who used dental services in the past year
The reference of central region and western region was eastern region, eastern region had higher economic development level
Nouns after “-” for variables indicated the references for binary variables
The UEBMI indicated urban employee basic medical insurance; the URBMI indicated urban resident basic medical insurance; the NRCMC indicated new rural cooperated medical care; other insurance included government medical insurance and private commercial insurance; they were binary variables in the decomposition and the reference was didn’t covered by such insurance

ISSN: 1472-6831