Table 2. The diagnostic performance of placenta subtype, intraoperative bleeding, and hysterectomy risk in the internal and external cohorts.

Classification task	AUROC	Sensitivity	Specificity	Cut-off value	Accuracy
Placenta subtype
Internal	0.93 (0.83–1.00)	0.79 (0.71–0.87)	0.99 (0.97–1.00)	0.51 (0.41–0.61)	0.85 (0.78–0.92)
External	0.91 (0.82–1.00)	0.80 (0.72–0.88)	0.90 (0.83–0.95)	0.61 (0.51–0.91)	0.83 (0.76–0.90)
Intraoperative bleeding
Internal	0.88 (0.74–1.00)	0.90 (0.84–0.96)	0.81 (0.72–0.88)	0.25 (0.16–0.34)	0.85 (0.79–0.93)
External	0.82 (0.68–0.96)	0.81 (0.73–0.89)	0.75 (0.67–0.84)	0.392 (0.29–0.49)	0.78 (0.70–0.86)
Hysterectomy risk
Internal	0.89 (0.77–1.00)	0.89 (0.83–0.95)	0.88 (0.82–0.94)	0.39 (0.30–0.48)	0.85 (0.77–0.91)
External	0.82 (0.67–0.97)	0.67 (0.58–0.76)	0.93 (0.88–0.98)	0.52 (0.42–0.62)	0.83 (0.77–0.90)

Data are presented as the numerical values of model performance parameters and their 95% confidence intervals. AUROC, area under the receiver operating characteristic curve.