Fig. 4

Validation of the GDM-M predictive model. A Receiver operating characteristic curve (ROC) validation of the GDM-M risk nomogram prediction. The y-axis represents the true positive rate of the risk prediction; the x-axis represents the false positive rate of the risk prediction; B Calibration curves of the predictive GDM-M risk nomogram. The y-axis represents actual diagnosed cases of GDM-M, the x-axis represents the predicted risk of GDM-M. The diagonal dotted line represents a perfect prediction by an ideal model, the solid line represents the performance of the GDM-M risk nomogram, with the results indicating that a closer fit to the diagonal dotted line represents a better prediction; C The clinical impact curve for the GDM-M predictive model. Of 1000 patients, the red solid line shows the total number who would be deemed high risk for each risk threshold. The blue dashed line shows how many of those would be true positives (cases). GDM-M, women with gestational diabetes mellitus and macrosomia. AUC, Area under the ROC curve; PPV, positive predictive value; NPV, negative predictive value