Intra‐ and interobserver variability of MRI prostate volume measurements

The Early Intervention Study, a placebo‐controlled clinical trial, enrolled approximately 200 patients between age 45–65 years who had mild symptoms associated with early benign hyperplasia (BPH). Prostate volume was measured by magnetic resonance imaging (MRI) and read by the local radiologist, who was blinded to the treatment group but not to the sequence of MRI scans. In order to ascertain whether knowledge of the sequence of the MRI scans by the local radiologist was introducing bias in prostate volume changes, a single radiologist was selected to reread all MRI scans at the end of the study.