Cumulative meta-analysis of the association between COMT Val158Met polymorphism and breast cancer susceptibility risk of the overall populations using a random effects model (dominant model LL+HL versus HH). Each study was used as an information step. The vertical dotted line is the summary odds ratio. Bars, 95% confidence interval (CI).
Qin et al. Diagnostic Pathology 2012 7:136 doi:10.1186/1746-1596-7-136