. 2020 May 6;16:128. doi: 10.1186/s12917-020-02345-z

Table 4.

The infection rate based on age groups

Province	Total	< 3 months			3–6 months			> 6 months			Chisq	p-value
Province	Total	n	Affected	Infection rate (%)	n	Affected	Infection rate (%)	Nn	Affected	Infection rate (%)	Chisq	p-value
Bac Giang	2350	545	86	15.8 ^a	608	167	27.5 ^b	1197	158	13.2 ^a	58.31	0.000
Ha Noi	1295	315	45	14.3 ^a	305	72	23.6 ^b	675	86	12.7 ^a	19.37	0.000
Hoa Binh	1954	528	64	12.1 ^a	352	91	25.8 ^b	1074	117	10.9 ^a	51.46	0.000
Ninh Binh	2435	587	93	15.8 ^a	623	173	27.8 ^b	1225	135	11.0 ^a	84.43	0.000
Nghe An	1798	404	63	15.6 ^a	441	119	27.0 ^b	953	126	13.2 ^a	41.09	0.000
Yen Bai	1856	419	41	9.8 ^a	492	98	19.9 ^a	945	80	8.5 ^a	42.89	0.000
Total	11,688	2798	392		2821	720		6069	702

Values between columns bearing similar superscript do not differ at p < 0.000

n number of animals