GST polymorphisms are associated with hepatocellular carcinoma risk in Chinese population

Table 3 Subgroup analysis of the association between GSTM1 polymorphism and hepatocellular carcinoma risk

Group	No. of studies (cases/controls)	Statistical method	OR (95% CI)	P
All studies	19 (2660/4017)	Random	1.487 (1.159-1.908)	0.002
Residence area of the subjects
High-incidence area	11 (1510/2666)	Random	1.659 (1.264-2.177)	0.000
Low-incidence area	7 (1040/1239)	Random	1.235 (0.753-2.026)	0.402
Mixed areas	1 (110/112)	-	1.602 (0.943-2.721)	0.081
No. of cases
< 100	9 (651/1262)	Random	1.676 (1.061-2.649)	0.027
≥ 100	10 (2009/2755)	Random	1.365 (1.005-1.853)	0.046
Source of controls
Population-based	9 (1489/1548)	Random	1.316 (0.915-1.892)	0.139
Hospital-based	10 (1171/2469)	Random	1.675 (1.251-2.243)	0.001

OR: Odds ratio.