Objective: This metaanalysis was undertaken to evaluate the relationship between tea intake and ovarian cancer risk.
Study design: A systematic literature search up to September 2006 was performed in Medline, Embase, CANCERLIT, and the Cochrane Database. The summary relative risk was calculated. A sensitivity analysis was conducted to test the influence of each single study. Heterogeneity and publication bias were also evaluated.
Results: Two cohort and 7 case-control studies were included. The combined relative risk did not show that tea consumption was associated with a reduced ovarian cancer risk (relative risk, 0.84; 95% confidence interval, 0.66-1.07). When the analyses were stratified into subgroups, there was no evidence that study design substantially influenced the estimate of effects. The sensitivity analysis which means removing one study at a time confirmed the stability of our results.
Conclusion: Our findings did not support that tea consumption was related to the decreased risk of ovarian cancer.