TABLE 5.

Subgroup difference-in-differences analyses (generalized linear regression) on unit price of procured cardiovascular medicines.

Subgroup	N	Intervention effect					Goodness-of-fit tests
		Coefficient	SE	Z	p>|z|	95%CI	AIC	BIC
Suppliers
Domestic suppliers outside of top 100	7,278	0.21	0.23	0.91	0.363	−0.25 to 0.67	10.83	−32,420.92
Top 100 domestic suppliers	1,157	−1.76	0.52	−3.42	0.001	−2.78 to -0.75	8.39	−5,462.00
Suppliers with joint venture	3,561	−0.51	0.60	−0.85	0.393	−1.69 to 0.66	10.99	−10,200.43
Foreign-owned suppliers	3,925	−0.08	0.06	−1.25	0.210	−0.20 to 0.04	6.84	−31,932.43
Medicines
Original brand	5,488	−0.36	0.13	-2.63	0.008	−0.62 to -0.09	6.59	-45,988.30
Generic	10,433	−0.28	0.18	−1.51	0.130	−0.64 to 0.08	11.32	-45,641.75
Administration route
Injectable	4,366	0.17	0.19	0.87	0.382	−0.21 to 0.54	14.29	−23,176.32
Oral	11,555	−0.08	0.06	−1.40	0.162	−0.19 to 0.03	4.63	−100,023.10

Note: Bold values indicate regression coefficients with statistical significance (p < 0.05). AIC - Akaike information criterion; BIC - Bayesian information criterion; CI - confidence interval; SE - product clustered standard error.