Association Between Service Agreements and Frequency of Primary Care Visits in a Chinese Community Health Service Center

Article Figures & Data

Table 1.

Characteristics of the Patient Population (n = 32,682)

Characteristics^*	Patients with Service Agreement (N = 21,699)	Patients without Service Agreement (N = 10,983)	P Value
Characteristics^*	n (%)	n (%)	P Value
Female	13,097 (60.4)	6,553 (59.7)	.23
Age group			<.01^f
18 to 39 years	1,109 (5.1)	1,172 (10.7)
40 to 59 years	7,386 (34.0)	4,343 (39.5)
60 to 79 years	10,261 (47.3)	3,988 (36.3)
80 years and older	2,943 (13.6)	1,480 (13.5)
Education level			<.01^f
< High school	5,295 (24.4)	2,451 (22.3)
High school and some college	9,038 (41.7)	4,354 (39.6)
Bachelor's degree and higher	7,366 (33.9)	4,178 (38.0)
Married	19,382 (89.3)	9,665 (88.0)	<.01^f
Employed	10,427 (48.1)	5,146 (46.9)	.04^{^‡}
Insured	18,725 (86.3)	8,391 (76.4)	<.01^f
Comorbidity, mean ± SE	2.6 ± 1.7	1.4 ± 1.5	<.01^f
Primary care visits, mean ± SE	10 ± 8.2	4.2 ± 5.0	<.01^f

SE, standard error.
↵* Values are number of subjects (weighted proportion) for categorical variables or weighted means (SE) for continuous variables.
† P values were calculated from χ² analysis or t-test (normally distributed) or Mann-Whitney U/Wilcoxon test (abnormally distributed) for continuous variables.
↵‡ P < .05; ^fP < .01.

Table 2.

Multivariate Logistic Regression for Prediction of Patients Signing Service Agreements

Characteristics	Estimate	SE	OR^*	95% CI
Female	0.137	0.026	1.147^{^‡}	(1.090, 1.207)
Age group (Reference: 18 to 39 years)
40 to 59 years	0.197	0.060	1.218^{^‡}	(1.082, 1.370)
60 to 79 years	0.720	0.061	2.055^{^‡}	(1.822, 2.318)
80 years and older	0.615	0.066	1.849^{^‡}	(1.624, 2.107)
Education (Reference: No High school)
High school and some college	0.162	0.034	1.176^{^‡}	(1.099, 1.257)
Bachelor's degree and higher	0.195	0.036	1.216^{^‡}	(1.133, 1.304)
Married	0.087	0.041	1.091^{^†}	(1.006, 1.183)
Employed	0.464	0.029	1.590^{^‡}	(1.502, 1.683)
Insured	0.605	0.033	1.832**	(1.717, 1.954)
Comorbidity	0.445	0.009	1.561**	(1.534, 1.589)

Table 3.

Effect of Gamma Regression on Primary Care Visits

Table 4.

Effects of the Service Agreement and Patient Characteristics on Primary Care Visits

Characteristics	Contrast	Estimate	SE	OR	95% CI
Sex
Female	SA vs non-SA	0.349	0.045	1.417^{^†}	(1.332, 1.508)
Male	SA vs non-SA	0.312	0.046	1.367^{^†}	(1.280, 1.459)
Age group
40 to 59 years	SA vs non-SA	0.436	0.028	1.547^{^†}	(1.493, 1.602)
60 to 79 years	SA vs non-SA	0.550	0.030	1.734^{^†}	(1.676, 1.794)
80 years and older	SA vs non-SA	0.467	0.041	1.595^{^†}	(1.517, 1.677)
Education
High school and some college	vs no-HS	−0.016	0.011	0.984	(0.963, 1.010)
Bachelor's degree and higher	vs no-HS	−0.061	0.011	0.941^{^†}	(0.920, 0.960)
Employed	vs Unemployed	−0.050	0.009	0.951^{^†}	(0.935, 0.970)
Insured	vs Uninsured	0.399	0.017	1.491^{^†}	(1.458, 1.524)
Comorbidity		0.347	0.004	1.415^{^†}	(1.407, 1.423)

CI, confidence interval; HS, high school; OR, odds ratio; SA, service agreement; SE, standard error.
* P values were from multiple 2-way interactions between SA and sex, and between SA and age group.
↵† P < .01.