Table 4. AUC-ROC calculations for spontaneous preterm birth (SPTB).

	Early and Late SPTB <38 weeks)	Early SPTB (<34 weeks)	Late SPTB (34-<38 weeks)
	A	B	C
Mean gest. age at sample collection	7.9±3.0 weeks	8.0±2.9 weeks	8.2±2.9 weeks
AUC-ROC	0.95	0.98	0.92
AUC-ROC 95% Confidence Interval	0.83–1.00	0.86–1.00	0.77–0.99
Preterm (14 total)	14	7	7
Full-term (25 total)	25	25	25
Sensitivity	86	100	86
Specificity	92	92	84
P value	P<0.0001	P<0.0001	P<0.0001