Table 4.

The PPVs according to different CNV sizes

CNV size	NIPT positive	TP	FP	Unverified	PPV (%)
≤ 5 Mb	37	5	19	13	20.83
Within 5–10 Mb	17	6	6	5	50.00
> 10 Mb	55	9	24	22	27.27
Total	109	20	49	40	28.99