Re: Coffee consumption and risk of prostate cancer: an up-to-date meta-analysis

Abstract

In their recent meta-analysis, Zhong et al.1 reported a 17% reduction in prostate cancer (PCa) risk when comparing highest versus non/lowest coffee consumption categories among 12 cohort studies1 (relative risk (RR)=0.83 (95% confidence interval (CI)=0.72–0.96)). Furthermore, they observed, from a dose-response meta-analysis, a 7% decreased risk of PCa for every two cups per day increase in coffee consumption (RR=0.93 (95% CI=0.88–0.99)). The authors also graphically presented that result in Figure 3b1. In the present letter, we would like to discuss two issues of that meta-analysis that we hope might draw attention to two fundamental steps of a meta-analysis: collection of the data and presentation of the results.