Drost FH, Nieboer D, Morgan TM, et al. - Data up to November 2017 from the Movember Foundation’s Global Action Plan consortium—a global collaboration between active surveillance (AS) studies—was used by experts to evaluate the external validity of two Canary Prostate AS Study Risk Calculators (PASS-RCs), which predict the likelihood of reclassification on a surveillance biopsy, via a mix of months since last biopsy, age, BMI, prostate-specific antigen, prostate volume, number of prior negative biopsies, and percentage (or ratio) of positive cores on last biopsy. Overall, the balance between detecting reclassification and performing surveillance biopsies was enhanced by both PASS-RCs, by decreasing unnecessary biopsies. Recalibration to the local setting will increase their clinical value and is, hence, needed prior to the implementation.