Table 4. Stratification for the test of heterogeneity on XPD Asp312Asn based on a recessive model.

	Q-test			I2, %	τ2	OR(95%CI)	P value
	chi-squared	d.f.	p
Overall	9.91	8	0.272	19.2	0.0354	1.48 (1.12–1.97)	0.007
Asians	4.58	5	0.470	0.0	0.0000	1.77 (1.19–2.63)	0.005
Caucasians	3.43	2	0.180	41.6	0.0587	1.31 (0.86–1.99)	0.211
Large sample	5.42	3	0.144	44.6	0.1053	1.35 (0.82–2.21)	0.239
Small-and-moderate sample	2.71	4	0.607	0.0	0.0000	1.74 (1.18–2.56)	0.005
High quality	8.55	5	0.128	41.5	0.0948	1.56 (1.05–2.33)	0.028
Low-and-moderate quality	1.36	2	0.508	0.0	0.0000	1.42 (0.85–2.40)	0.184
High quality Asians	1.68	2	0.433	0.0	0.0000	2.37 (1.29–4.36)	0.005
High quality Caucasians	3.43	2	0.180	41.6	0.0587	1.31 (0.86–1.99)	0.211
Publication before or in 2007	4.34	3	0.227	30.9	0.1128	1.61(0.89–2.92)	0.115
Publication after 2007	5.41	4	0.248	26.0	0.0452	1.46 (1.02–2.09)	0.041
Cardia type	0.85	2	0.654	0.0	0.0000	0.89 (0.56–1.43)	0.642
PCR-RFLP genotyping	6.59	4	0.159	39.3	0.1474	1.90 (1.09–3.31)	0.023
Direct sequencing	0.02	1	0.902	0.0	0.0000	1.24 (0.70–2.20)	0.450

Only D+L ORs (95% CI) and P values of D+L estimates provided.