title: Nuchal translucency and first trimester biochemical markers for down syndrome screening: a cost-effectiveness analysis.
abstract: OBJECTIVE
  The purpose of this study was to perform a cost-effectiveness analysis that compared the first- and second- trimester screening tools for Down syndrome.
  
  
  METHODS
  A decision tree was designed that compared four possible screens for Down syndrome: (1) current second- trimester expanded maternal serum alpha-fetoprotein test (AFP), (2) first-trimester nuchal translucency screen, (3) first-trimester serum screen, and (4) combined first-trimester screen with both nuchal translucency screen and a serum screen. Incremental cost-benefit and cost-effectiveness ratios were calculated that compared the first-trimester screens with expanded alpha-fetoprotein.
  
  
  RESULTS
  The combined screen (nuchal translucency screen + first-trimester serum screen) identified 3,833 Down syndrome fetuses, the nuchal translucency alone identified 3,413 Down syndrome fetuses, and the first- trimester serum screen identified 2,993 Down syndrome fetuses. Each of these screens was an improvement over the current expanded AFP screen, which diagnosed 2,446 Down syndrome fetuses. It would cost $98,381 for each additional Down syndrome case that would be identified by nuchal translucency alone, with a benefit-to-cost ratio of 4.85. The addition of the first-trimester serum screen is still cost-effective compared with expanded AFP; the cost would be $319,934 for each additional Down syndrome fetus who was identified, which would be a benefit-to-cost ratio of 1.57.
  
  
  CONCLUSIONS
  First-trimester screening for Down syndrome with nuchal translucency screening alone or with serum markers is more clinically effective and cost-effective than the current expanded AFP screen that is being used.
authors.affiliation: Department of Obstetrics and Gynecology, University of California, San Francisco, USA. abcmd@uclink.berkeley.edu
authors.forename: Aaron B
authors.initials: AB
authors.lastname: Caughey
authors.forename: Miriam
authors.initials: M
authors.lastname: Kuppermann
authors.forename: Mary E
authors.initials: ME
authors.lastname: Norton
authors.forename: A Eugene
authors.initials: AE
authors.lastname: Washington
mesh_terms: D003362:Cost-Benefit Analysis; D004314:Down Syndrome / Q000175:diagnosis / Q000000981:diagnostic imaging*; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D006801:Humans; D008403:Mass Screening / Q000191:economics* / Q000379:methods*; D009333:Neck / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D016216:Ultrasonography, Prenatal / Q000191:economics*; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D000509:alpha-Fetoproteins