Frontomaxillary Facial Angle Measurement in Screening for Trisomy 18 at 11 + 0 to 13 + 6 Weeks of Pregnancy: A Double-Centre Study

Table 3

Model 2—as in Model 1 plus the FMF angle.

Risk	1 : 300	1 : 200	1 : 100	1 : 50
DR (%)	93.3	90.0	87.0	87.3
FPR (%)	1.3	1.1	0.9	0.8
PPV (%)	96.2	96.3	99.8	99.8
NPV (%)	99.2	99.2	99.6	99.6
LR+	425.83	428.58	476.94	476.94
LR−	0.17	0.16	0.07	0.07
𝑃 value	<0.0001	<0.0001	<0.0001	<0.0001