EDITORIAL COMMENT

There was no stone scoring system for preoperative patient counseling and standardization until Guy’s stone score was developed in 2011. S.T.O.N.E Nephrolithometry and Clinical Research Office of Endourological Society nomogram have been developed, respectively. The present study is the largest multicenter cohort study including 586 patients, retrospectively evaluating and comparing these three scoring systems at four academic institutions. The authors reported similar results regarding estimation of stone-free rates (SFR) with all the three scoring systems after a single session percutaneous nephrolitotomy (PCNL). They also noted that none of these scoring systems have significantly added predictive accuracy over stone size alone as a predictor of SFR. The patients were stratified into low-, intermediate-, high- and very high-risk groups for relative risk for residual stone for all scoring systems and it was seen that residual stone risk after PCNL surgery increases with increased risk group stratification. With regard to complications, none of the scoring systems strongly predicted complications. Only S.T.O.N.E score was found to be an independent predictor of operation time. As a result, all the three scoring systems are useful and equally effective in prediction of SFR despite specific limitations. Urological surgeons may benefit from these scoring systems for estimating case complexity and preoperative patient counseling. Further researches on scoring systems are mandatory especially for prediction of complications.