Table 2.

Features used by the models in this study compared to those from previous studies.^a

Source			Gestational age at prediction		Features, n (for maternal characteristics) or + (used by the model) or – (not used by the model)
					Maternal characteristics		MAPb		PI-UtAc		Bilateral notch		sFlt-1d		PlGFe		PAPP-Af
This study
	CVRg1 (right PI-UtA)	24-37 weeks		2		–		+		–		+		+		–
	CVR2 (mean PI-UtA)	24-37 weeks		2		–		+		+		+		+		–
	CVR3 (lowest PI-UtA)	24-37 weeks		2		–		+		–		+		+		–
	158-tree random forest	24-37 weeks		1		–		+		+		+		+		–
Previous studies
	Wright A et al (2019) [26]	11-13 weeks		10		–		+		–		+		+		–
	Wright D et al (2019) [27]	11-13 weeks		11		+		+		–		+		+		–
	Tan MY et al (2018) [25]	11-13 weeks		11		+		+		–		–		+		–
	Sonek J et al (2018) [24]	11-13 weeks		10		–		+		–		–		+		+
	Perales A et al (2017) [23]	27-28 weeks		3		+		–		–		+		+		–
	Nuriyeva G et al (2017) [22]	11-13 weeks		N/Ah		–		+		–		–		+		+
	O'Gorman N et al (2017) [21]	11-13 weeks		11		+		+		–		–		+		+
	Gallo DM et al (2016) [18]	19-24 weeks		11		+		+		–		+		+		–
	Tsiakkas A et al (2016) [19]	30-34 weeks		11		–		–		–		+		+		–
	Andrietti S et al (2016) [20]	35-37 weeks		11		+		+		–		+		+		–
	O'Gorman N et al (2016) [17]	11-13 weeks		10		+		+		–		–		+		+
	Wright D et al (2015) [16]	11-13 weeks		11		–		–		–		–		–		–

^aModels that showed the best sensitivity and an acceptable specificity in each study.

^bMAP: mean arterial pressure.

^cPI-UtA: pulsatility index of the uterine artery.

^dsFlt-1: soluble fms-like tyrosine kinase receptor-1.

^ePlGF: placental growth factor.

^fPAPP-A: pregnancy-associated plasma protein-A.

^gCVR: classification via regression.

^hN/A: not applicable.