Table 3. Characteristics of the Studies about the XRCC1 Arg280His polymorphism (rs25489) Included in the Meta-analysis.

Author	Year	Ethnicity	Cancer Site	Genotyping Method	Control Source	Matching Criteria	Adjusted Variables	Case				Control				HWEc	MAFd
								N	AA	AB	BB	N	AA	AB	BB
Majumder	2005	Asian	Oral	PCR-RFLP	HBa	None	None	310	228	79	3	348	264	81	3	0.232	0.125
Harth	2008	Caucasian	Head&neck	RT-PCR	HB	None	Age, sex	312	283	28	1	300	270	30	0	0.362	0.050
Applebaum	2009	Mixed	Head&neck	PCR-RFLP	PBb	Age, sex	Age, sex, race, education, smoke, alcohol, HPV16	484	437	46	1	548	492	52	4	0.052	0.055
Majumder	2007	Asian	Oral	PCR-RFLP	HB	None	Age, sex, smoke	307	225	79	3	387	297	87	3	0.213	0.120
Tae	2004	Asian	Head&neck	MAPA	HB	None	Age, smoke, alcohol	135	113	21	1	168	139	29	0	0.221	0.086
Ramachandran	2006	Asian	Oral	PCR-RFLP	PB	Age, sex	Age, sex, smoke, alcohol, betel quid chewing	110	77	31	2	110	83	26	1	0.502	0.127
Kumar	2012	Asian	Head&neck	PCR-RFLP	PB	Age, sex, habits	None	278	129	123	26	278	142	116	20	0.575	0.281
Gugatschka	2011	Caucasian	Head&neck	TaqMan	PB	None	None	168	159	9	0	463	430	32	1	0.621	0.037
Ho	2007	Mixed	Oral	PCR-RFLP	HB	None	Age, sex, ethnicity, family history, smoke, alcohol, radiation exposure	138	125	13	0	503	453	50	0	0.241	0.050

^aHB: Hospital based;

^bPB: Population based;

^cHWE: Hardy-Weinberg equilibrium in controls;

^dMAF: Minor allele frequency in controls.