Summary ORs (95% CI) and value of value of the heterogeneity of XRCC1 Arg399Gln polymorphism for studies according to source of controls and cancer type1.

1all summary ORs were calculated using fixed-effects models. In the case of significant heterogeneity (indicated by *), ORs were calculated using random-effects models;2the results were excluded due to high heterogeneity;3total breast cancer comparisons add up to 53 (which should be 54) because there was one study that we can not determine hospital-based study, population-based study or family-based study. The reason is same with colorectal cancer, prostate cancer and so on; PB, population-based study; HB, hospital-based study; SZ Sample size. The bold values indicate that the results are statistically significant.