Table 2.

Results of meta-analysis for XPD Asp312Asn polymorphism and esophageal cancer risk

Study group	N	Asn/Asp vs. /Asp/Asp		Asn/Asn vs. Asp/Asp		(Asn/Asp+Asn/Asn) vs. Asp/Asp		Asn/Asn vs. (Asn/Asp+Asp/Asp)
		OR (95%) CI	P/P#	OR (95%) CI	P/P#	OR (95%) CI	P/P#	OR (95%) CI	P/P#
Total	15	1.06 [0.72, 1.57]	0.01/1.00	1.27 [0.99, 1.62]	0.06/0.95	1.14 [1.03, 1.27]	0.01/1.00	1.16 [0.92, 1.46]	0.22/0.94
Cancer type
ESCC	11	1.13 [0.99, 1.28]	0.07/0.99	1.29 [0.90, 1.86]	0.16/0.99	1.12 [0.99, 1.27]	0.08/0.99	1.18 [0.84, 1.66]	0.34/0.99
EADC	4	1.20 [0.98, 1.48]	0.08/0.95	1.21 [0.88, 1.68]	0.24/0.32	1.20 [0.99, 1.47]	0.06/0.90	1.10 [0.81, 1.49]	0.55/0.30
Ethnicity
Asian	9	1.10 [0.95, 1.28]	0.20/0.99	1.64 [0.67, 3.98]	0.28/0.97	1.08 [0.94, 1.26]	0.28/1.00	1.62 [0.66, 3.93]	0.29/0.97
European	5	1.20 [0.99, 1.45]	0.06/0.92	1.13 [0.83, 1.52]	0.44/0.56	1.18 [0.99, 1.42]	0.07/0.90	1.02 [0.77, 1.36]	0.87/0.56
Control source
PB	10	1.12 [0.91, 1.38]	0.27/0.96	1.23 [0.76, 2.00]	0.40/0.97	1.13 [0.93, 1.39]	0.22/0.96	1.84 [0.82, 4.12]	0.14/< 0.05
HB	5	1.16 [1.02, 1.32]	0.02/0.98	1.25 [0.95, 1.66]	0.11/0.69	1.15 [1.01, 1.30]	0.03/0.97	1.13 [0.86, 1.46]	0.38/0.65
Smoking
Yes	3	1.33 [0.79, 2.24]	0.28/0.52	1.10 [0.17, 7.12]	0.92/0.32	1.63 [1.06, 2.50]	0.03/0.31	1.06 [0.16, 6.86]	0.95/0.33
No	3	1.02 [0.67, 1.57]	0.91/0.73	2.31 [0.40, 13.34]	0.35/0.18	3.29 [0.39, 8.05]	0.28/< 0.05	2.29 [0.40, 13.22]	0.35/0.18

N, number of studies;

^#Test for heterogeneity, Random-effect model was used when the P value was <0.05, otherwise the fixed-effect model was used;

OR, odds ratio; CI, confidence interval; ESCC, Esophageal Squamous Cell Carcinoma; EADC, Esophageal Adenocarcinoma; HB, Hospital-based; PB, Population-based.