**3. Review of 5-ARI chemoprevention trials**

We reviewed the multicenter randomized double blind studies focused on 5-ARI usage versus placebo for prostate cancer chemoprevention including the Prostate Cancer Prevention Trial (PCPT) and the Reduction by Dutasteride of Prostate Cancer Events (REDUCE). Table 1 compares their study design.


Table 1. Comparison of PCPT & REDUCE trials.
