Soukup , V , Čapoun , O , Cohen , D , Hernandez , V , Babjuk , M , Burger , M , Compérat , E , Gontero , P , Lam , T , MacLennan , S , Mostafid , A H , Palou , J , van Rhijn , B W G , Rouprêt , M , Shariat , S F , Sylvester , R , Yuan , Y & Zigeuner , R 2017 , ' Prognostic Performance and Reproducibility of the 1973 and 2004/2016 World Health Organization Grading Classification Systems in Non–muscle-invasive Bladder Cancer : A European Association of Urology Non-muscle Invasive Bladder Cancer Guidelines Panel Systematic Review ' European Urology , vol. 72 , no. 5 , pp. 801-813 . DOI: 10.1016/j.eururo.2017.04.015