Table 2.

Detection rates and false positive rates of different Down syndrome screening tests (43, 44)

Test	Markers of aneuploidy	Trimester	DR (%)	FPR (%)
NT alone	NT	1st	64-70	5
Combined	NT+ PAPP-A + β-hCG	1st	65	5
Triple screen	β-hCG + AFP + estriol	2nd	70	14
Quad screen	β-hCG + AFP + estriol+ inhibinA	2nd	81	7
Serum Integrated	β-hCG +AFP +estriol+ inhibinA + PAPP-A	1st and 2nd	85-88	5
Integrated	NT + β-hCG + AFP + estriol+ inhibinA + PAPP-A	1st and 2nd	94-96	1
Sequential	NT + β-hCG +AFP + estriol+ inhibinA + PAPP-A	1st and 2nd	95	2

DR: detection rate; FPR: false-positive rate; NT: nuchal translucency; PAPP-A: pregnancy-associated plasma protein- A; β-hCG: chorionic gonadotropin; AFP: alpha-fetoprotein