Table 3

Main characteristics of studies of cyclo-oxygenase-2 G-765C polymorphism and the risk of hepatocellular carcinoma

Study	Country	Source of control	Genotyping method	P_HWE	Cases/ controls	No. of cases			No. of controls
Study	Country	Source of control	Genotyping method	P_HWE	Cases/ controls	GG	GA	AA	GG	GA	AA
Akkiz et al10	Turkey	HB	PCR-RFLP	0.009	129/129	4	46	79	15	39	75
Chang et al11	Taiwan	PB	PCR-RFLP	0.13	298/298	0	36	262	0	48	250
Gharib et al13	Egypt	PB	PCR-RFLP	0.58	120/100	4	30	86	6	39	85
He et al18	China	PB	PCR-RFLP	0.59	300/300	10	67	223	2	37	261
Li and Meng14	China	HB	PCR-RFLP	0.60	178/196	0	26	152	0	14	182
Xu et al17	China	PB	PCR-RFLP	0.58	270/540	0	37	233	0	25	515

HB, hospital-based; PB, population-based; PCR-RFLP, PCR-restriction fragment length polymorphism; P_HWE, Hardy–Weinberg equilibrium of controls.