Ma YC, Jian ZY, Li H, et al. - A propensity score matching analysis was conducted to compare preoperative urine nitrite with urine culture for predicting postoperative fever following flexible ureteroscopic lithotripsy. Between 2009 and 2019, researchers screened patients who had undergone flexible ureteroscopy (fURS) by the same surgeon. They estimated sensitivity and specificity of urine culture and urine nitrite. They conducted propensity score matching to get a baseline-balanced retrospective cohort to avoid potential bias. Using receiver operating characteristic-area under the curve, the predictive power of models was ascertained. They plotted decision curve analysis to collect the clinical benefit of the models. It demonstrates that preoperative positive urine nitrite may play a pivotal role in the prediction of postoperative fever after fURS and requirements to be confirmed by future evidence.