title: Repeat testing in antenatal screening for Down syndrome using dimeric inhibin-A in combination with other maternal serum markers.
abstract: The effect on screening performance of collecting a second fresh blood sample in antenatal screening for Down syndrome has been previously reported for the commonly used double and triple tests. Recently, dimeric inhibin-A has been used with the triple test (together constituting the quadruple test) in several centres and here we assess the effect of repeat testing using inhibin-A. Routine repeat testing using the quadruple test did not yield a material increase in performance compared with having no repeat testing. For a 5% false-positive rate the increase in detection rate was only about 3-5 percentage points; a modest increase which is probably not worthwhile in the light of the extra cost and delay.
authors.affiliation: Department of Environmental & Preventive Medicine, Wolfson Institute of Preventive Medicine, St Bartholomew's & The Royal London School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, UK.
authors.forename: A K
authors.initials: AK
authors.lastname: Hackshaw
authors.forename: N J
authors.initials: NJ
authors.lastname: Wald
mesh_terms: D015415:Biomarkers / Q000097:blood*; D006063:Chorionic Gonadotropin / Q000097:blood; D004314:Down Syndrome / Q000097:blood / Q000175:diagnosis*; D004964:Estriol / Q000097:blood; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007265:Inhibins / Q000097:blood*; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012680:Sensitivity and Specificity; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D015415:Biomarkers; D006063:Chorionic Gonadotropin; D000509:alpha-Fetoproteins; D007265:Inhibins; D004964:Estriol