. 2012 Aug 28;4(5):938–948. doi: 10.3892/etm.2012.687

Table I.

Characteristics of the studies included in this meta-analysis.

Author (Refs.)	Site	Group	Source	Sample	Genotype			Genotyping method	P-value (HWE) for controls	Adjustment
Author (Refs.)	Site	Group	Source	Sample	c1/c1	c1/c2	c2/c2	Genotyping method	P-value (HWE) for controls	Adjustment
Lin et al (16)	Linxian County, Henan Province	T	ESCC and EAC	45	36	6	3	PCR-RFLP	0.345	Age, gender
Lin et al (16)	Linxian County, Henan Province	C	PB	45	20	22	3	PCR-RFLP	0.345	Age, gender
Tan et al (17)	Linxian County, Henan Province	T	ESCC	150	107	31	12	PCR-RFLP	0.009	Age, gender, smoking
Tan et al (17)	Linxian County, Henan Province	C	PB	150	66	77	7	PCR-RFLP	0.009	Age, gender, smoking
Shi (20)	Linzhou City, Henan Province	T	EC	116	74	37	5	PCR-RFLP	0.922	Age, gender, smoking, fermented vegetable
Shi (20)	Linzhou City, Henan Province	C	HB	106	46	48	12	PCR-RFLP	0.922	Age, gender, smoking, fermented vegetable
	Xi’an City, Shaanxi Province	T	EC	71	39	28	4	PCR-RFLP	0.368
	Xi’an City, Shaanxi Province	C	HB	62	30	24	8	PCR-RFLP	0.368
Gao et al (21)	Huai’an City, Jiangsu Province	T	EC	144	83	44	13	PCR-RFLP	0.525	Age, gender, tea, smoking, alcohol
Gao et al (21)	Huai’an City, Jiangsu Province	C	PB	233	140	75	14	PCR-RFLP	0.525	Age, gender, tea, smoking, alcohol
Shi et al (23)	Wuhan City, Hubei Province	T	EC	98	72	19	7	PCR-RFLP	0.039	Age, gender
Shi et al (23)	Wuhan City, Hubei Province	C	HB	120	54	45	21	PCR-RFLP	0.039	Age, gender
Gao et al (22)	Huai’an City, Jiangsu Province	T	EC	93	55	31	7	PCR-RFLP	0.20	Age, gender, smoking, drinking, dietary habits
Gao et al (22)	Huai’an City, Jiangsu Province	C	PB	196	121	62	13	PCR-RFLP	0.20	Age, gender, smoking, drinking, dietary habits
Shi et al (24)	Nanjing City, Jiangsu Province	T	EC	78	48	24	6	PCR-RFLP	0.141	Age, gender, smoking, alcohol
Shi et al (24)	Nanjing City, Jiangsu Province	C	HB	118	60	42	16	PCR-RFLP	0.141	Age, gender, smoking, alcohol
Yin et al (25)	Huai’an City, Jiangsu Province	T	EC	106	52	49	5	PCR-RFLP	0.411	Age, gender
Yin et al (25)	Huai’an City, Jiangsu Province	C	HB	106	55	45	6	PCR-RFLP	0.411	Age, gender
Lu et al (19)	Kazakh, Xinjiang Autonomous Region	T	ESCC	104	81	20	3	PCR-RFLP	<0.001	Age, gender
Lu et al (19)	Kazakh, Xinjiang Autonomous Region	C	PB	104	25	74	5	PCR-RFLP	<0.001	Age, gender
Li (26)	Taiyuan City, Shanxi Province	T	EC	60	32	18	10	PCR-RFLP	0.781	Age, gender, smoking, drinking habits
Li (26)	Taiyuan City, Shanxi Province	C	PB	199	101	69	29	PCR-RFLP	0.781	Age, gender, smoking, drinking habits
Liu et al (28)	Huai’an City, Jiangsu Province	T	ESCC	77	34	33	10	PCR-RFLP	0.91	Age, gender
Liu et al (28)	Huai’an City, Jiangsu Province	C	PB	79	45	29	5	PCR-RFLP	0.91	Age, gender
Dong et al (27)	Gansu Province	T	EC	120	84	26	10	PCR-RFLP	0.428	Age, gender
Dong et al (27)	Gansu Province	C	HB	120	57	44	19	PCR-RFLP	0.428	Age, gender
Xia et al (31)	Jingjiang City, Jiangsu Province	T	ESCC	45	30	12	3	PCR-RFLP	0.708	Not reported
Xia et al (31)	Jingjiang City, Jiangsu Province	C	HB	45	26	17	2	PCR-RFLP	0.708	Not reported
Qin et al (30)	Kazakh, Xinjiang Autonomous Region	T	EC	120	94	23	3	PCR-RFLP	0.29	Age, gender, dietary habits
Qin et al (30)	Kazakh, Xinjiang Autonomous Region	C	PB and HB	240	128	90	22	PCR-RFLP	0.29	Age, gender, dietary habits
Guo et al (29)	Lanzhou City, Gansu Province	T	ESCC	80	57	16	7	PCR-RFLP	<0.001	Age, gender
Guo et al (29)	Lanzhou City, Gansu Province	C	PB	480	225	180	75	PCR-RFLP	<0.001	Age, gender
Yang (32)	Feicheng City, Shandong Province	T	ESCC	27	19	8	0	PCR-RFLP	0.442	Age, gender, alcohol, education, smoking
Yang (32)	Feicheng City, Shandong Province	C	PB	44	31	11	2	PCR-RFLP	0.442	Age, gender, alcohol, education, smoking
Zhang and Wu (33)	Gansu Province	T	EC	129	75	40	14	PCR-RFLP	0.443	Age, gender
Zhang and Wu (33)	Gansu Province	C	PB	156	70	56	21	PCR-RFLP	0.443	Age, gender

Characteristics of studies included in this meta-analysis. T, case subjects; C, control subjects; PB, population-based; HB, hospital-based; ESCC, esophageal squamous cell carcinoma; EAC, esophageal adenocarcinoma; EC, esophageal cancer; HWE, Hardy-Weinburg equilibrium; PCR-RFLP, polymerase chain reaction-restriction fragment length polymorphism.