Test ID: QUAD
Quad Screen (Second Trimester) Maternal, Serum
Method Description
Describes how the test is performed and provides a method-specific reference
The 4-marker screen includes alpha-fetoprotein (AFP), estriol (uE3), human chorionic gonadotropin (total beta-hCG [ThCG]), and inhibin A. Analyte values are compared to median values at a given gestational age and multiple of the median (MoM) results obtained. The MoM results are used in a multivariate algorithm that includes the mother's age to derive risk factors for Down syndrome and trisomy 18. The screen for NTD uses the AFP MoM only. An interpretive report is provided. The Beckman Access AFP, ThCG, uE3, and inhibin A assays are automated immunoenzymatic assays with paramagnetic separation and chemiluminescent detection. (Package insert: Beckman Coulter Access AFP, Total bhCG, Unconjugated Estriol, and Inhibin A. 2010)
Day(s) and Time(s) Test Performed
Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 5 a.m.-5 p.m., Saturday; 6 a.m.-1 p.m.


