Table 2 Results of overall and stratified analyses for the association of XRCC1 399 G → A and risk of glioma, all eligible studies
Stratification factor | No. of studies | I 2(%) | Odds ratio | 95% Confidence interval | P value |
|---|---|---|---|---|---|
Overall | 6 | 87 | 1.17 | 1.05-1.30 | 0.006 |
Gender | |||||
Male | 1 | NA | 0.94 | 0.62-1.44 | 0.78 |
Female | 1 | NA | 2.27 | 1.45-3.57 | < 0.001 |
Glioma Subtype | |||||
Grade III | 2 | 0 | 1.05 | 0.89-1.25 | 0.56 |
Grade IV | 2 | 46 | 1.20 | 0.97-1.47 | 0.09 |
Sample size | |||||
< 500 | 2 | 92 | 3.09 | 2.06-4.65 | < 0.001 |
≥ 500 | 4 | 0 | 1.08 | 0.96-1.21 | 0.19 |
Country | |||||
US | 3 | 8 | 1.11 | 0.94-1.31 | 0.22 |
Other | 3 | 94 | 1.22 | 1.05-1.42 | 0.009 |
Genotyping method | |||||
PCR-RFLP | 4 | 92 | 1.16 | 1.01-1.32 | 0.03 |
Other | 2 | 0 | 1.19 | 0.97-1.46 | 0.09 |