Reply from Authors re: Monique J. Roobol. Prostate Cancer Biomarkers to Improve Risk Stratification: Is Our Knowledge of Prostate Cancer Sufficient to Spare Prostate Biopsies Safely? Eur Urol 2011;60:223-5 and re: Carvell T. Nguyen, Michael W. Kattan. How to Tell If a New Marker Improves Prediction. Eur Urol 2011;60:226-8