Development and validation of a predictive nomogram for urethral plate transection in Chinese patients with hypospadias

To develop and validate a predictive model for transecting urethral plate (UP) in Chinese patients with hypospadias surgery. A total of 860 children with primary hypospadias from Children’s Hospital of Fudan University from January 2019 to December 2022 and 368 children with primary hypospadias from Renji Hospital, School of Medicine, Shanghai Jiao Tong University from January 2021 to June 2023 were retrospectively analyzed and divided into a training set and a validation set. Multivariate logistic regression analysis was used to identify the predictors, and a nomogram model was constructed to predict the operation of UP transection in the training set. Use area under the curve(AUC), calibration curve(CC), decision curve analysis(DCA) and clinical impact curve(CIC) evaluated the predictive accuracy and clinical benefit of the nomogram model. Multivariable logistic regression analysis showed that meatus position(MP), penile curvature(PC), penis diameter(PD) and urethral defect/stretched penile length(UDR) were independent predictors for UP transection in hypospadias surgery. The AUC of the nomogram in the training set and validation set were 0.810 and 0.791, respectively. The CC of the nomogram was close to the ideal diagonal line. Furthermore, the DCA and CIC demonstrated significantly better net benefit in the model. The internal and external validation groups proved the reliability of the predictive nomogram. This study demonstrated that MP, PC, PD and UDR were significant predictors of UP transection in Chinese patients with hypospadias surgery. This may guide surgical decision-making and treatment.