Improvements in antenatal screening for Down's syndrome
نویسندگان
چکیده
OBJECTIVES To estimate improvements to four antenatal screening tests for Down's syndrome (first trimester Combined, second trimester Quadruple, and first and second trimester Integrated and Serum Integrated tests) based on adding ductus venosus pulsatility index (DVPI), fetal nasal bone examination (NBE) and serum placental growth factor (PlGF). SETTING Statistical analysis of data from several sources modelled using the maternal age distribution of live births in England and Wales from 2006 to 2008. METHODS Monte Carlo simulation carried out to estimate the screening performance of tests with the addition of combinations of DVPI, NBE and PlGF. RESULTS At a 95% detection rate (DR), with first trimester markers measured at 11 completed weeks' gestation, the addition of DVPI, NBE and PlGF decreased the false-positive rate (FPR) of the Combined test from 16.1% to 3.0%, the addition of PlGF to the Quadruple test decreased the FPR from 15.7% to 15.3%, the addition of DVPI, NBE and PlGF to the Integrated test decreased the FPR from 4.1% to 0.6% and the addition of PlGF to the Serum Integrated test decreased the FPR from 15.1% to 11.1%. At a 90% detection rate, the reductions in the FPR were from 6.8% to 0.8%, 7.7% to 7.4%, 1.2% to 0.1% and 6.2% to 4.8%, respectively. CONCLUSIONS The addition of DVPI, NBE and PlGF to the Combined and Integrated tests significantly improves screening performance, reducing the FPRs by over 80%. The Integrated test with DVPI, NBE and PlGF is significantly better than the Combined test with DVPI, NBE and PlGF.
منابع مشابه
Trends in Down’s syndrome live births and antenatal diagnoses in England and Wales from 1989 to 2008: analysis of data from the National Down Syndrome Cytogenetic Register
OBJECTIVES To describe trends in the numbers of Down's syndrome live births and antenatal diagnoses in England and Wales from 1989 to 2008. Design and setting The National Down Syndrome Cytogenetic Register holds details of 26488 antenatal and postnatal diagnoses of Down's syndrome made by all cytogenetic laboratories in England and Wales since 1989. INTERVENTIONS Antenatal screening, diagnos...
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syndrome. In: Grudzinskas JG, Chard T, Chapman M, Cuckle HS, eds. Cambridge: Cambridge University Press, 1993 (in press). 25 Laundon C, Spencer K, Macri JN, Buchanan P. Tumer syndrome detection by MSAFP/Free Beta (hCG) screening. J Med Genet 1993;30:340-1. 26 Spencer K, Mallard AS, Coombes EJ, Macri JN. Prenatal screening for trisomy 18 with free f3 human chorionic gonadotrophin. BMJ 1993 (in p...
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