Table 9.

Validity (AUC, sensitivity, specificity) for cervical length and uterocervical angle to predict preterm birth at 2^nd visit (n = 22 vs. 48)

At 2nd Visit	AUC	P	95% CI	Cut off	Sensitivity	Specificity	PPV	NPV
Cervical length (mm)	0.743	0.001*	0.609—0.877	≤ 3.22	68.18	62.50	45.5	81.1
Cervical length (mm)				≤ 2.56**	13.64	100.00	100.00	71.6
Uterocervical Angle ( °)	0.866	< 0.001*	0.761 – 0.971	> 89.81	81.82	70.83	56.3	89.5

AUC Area under curve, CI Confidence intervals, PPV Positive predictive value, NPV Negative predictive value, *: statistically significant at p ≤ 0.05

^**This cutoff value is added for comparison as the nearest value in the study population to the standard 25-mm cutoff for short cervix