Fig. 2

Nomogram development and validation (Overall survival). A: The nomogram incorporates five variables, with points allocated according to the scale for each variable. A total score was awarded from the sum of the individual scores, and used to calculate the predicted overall survival (OS) of pregnant patients with PH at 1, 2, and 3 years. B (a, b): ROC curve of the 1, 2, and 3-year survival predictions in the Follow-up (a) and (follow-up) Validation sets (b). The red, blue, and orange lines represent the AUC of the ROC curves for 1, 2, and 3 years, respectively. C (a, b): Decision curve analysis for the prognostic nomogram in the Follow-up (a) and (follow-up) Validation sets (b). The y-axis indicates the net benefit, which is the sum of the benefits (true positives) minus harm (false positives). The x-axis indicates the threshold probability. The red, blue, and orange lines represent the 1, 2, and 3-year survival benefits, respectively. AUC area under the curve, NT-proBNP N-terminal pro-brain natriuretic peptide, NYHA New York Heart Association, PH pulmonary hypertension, RF respiratory failure, ROC receiver operating characteristic