Abstract:Objective To construct a prediction model for the risk of peripherally inserted central venous catheter (PICC)-related bloodstream infection (CRBSI) in preterm infants, and evaluate the effect of the model. Methods 1 295 preterm infants admitted to the neonatal intensive care unit (NICU) in a hospital and received PICC intravenous infusion from January 2019 to October 2023 were selected as the study subjects, including 1 080 preterm infants from January 2019 to December 2022 in the modeling set and 215 premature infants from January to October 2023 in the validation set.Risk factors of cases were analyzed based on 24 clinical characteristics, optimized characteristics was selected by LASSO regression, independent risk factors for CRBSI of preterm infants during PICC indwelling period were identified by multiple logistic regression analysis, and nomogram model was constructed with R software. Discrimination and fitting of the model were evaluated by the area under the curve (AUC) of the receiver operating characteristic (ROC) as well as Hosmer-Lemeshow test and calibration curve, and clinical practicality of the model was evaluated by decision curve analysis (DCA). Results Multivariate logistic analysis showed that birth weight ≥1 500 g, sterile protection during catheter maintenance, and sterile cloth wrapped joints were protective factors for CRBSI during PICC indwelling period in preterm infants (OR=0.172, 0.187, 0.063, respectively, all P<0.05), while puncture frequency ＞2 times, catheter indwelling period ＞14 days, and use of tees were independent risk factors for CRBSI during PICC indwelling period in premature infants (OR=2.533, 14.128, 13.256, respectively, all P<0.05). The AUC of ROC of the modeling set was 0.953 (95%CI: 0.936-0.969), and that of the validation set was 0.930 (95%CI: 0.885-0.974), indicating good discriminability of the model. The calibration curve and Hosmer-Lemeshow goodness of fit test showed that the model had good accuracy and consistency, with high net profit value, indicating that the predictive value of the model was high and with good clinical practica-lity. The statistical test result in the rationality analysis of the model was P<0.001. Conclusion The nomogram model based on the general clinical characteristics of preterm infants as well as the basic prevention and control measures of the catheter can provide a visual and simple evaluation tool for early identification of high risk factors for CRBSI in preterm infants.