title: Rapid prenatal diagnostic testing for Down syndrome only or longer wait for full karyotype: the views of pregnant women.
abstract: OBJECTIVE
  Prenatal diagnosis by karyotype analysis determines the copy number and structure of each chromosome and is considered to be the 'gold standard' in detection of chromosome abnormality. This method is, however, time consuming and women may have to wait up to 21 days for the results. With improving molecular genetic techniques, the most commonly occurring chromosome abnormalities can be diagnosed within 2 days from amniotic fluid. This study investigates the value pregnant women place on these alternative prenatal diagnostic tests.
  
  
  METHODS
  A structured self-completion discrete choice experiment questionnaire was designed. The subjects were 40 pregnant women, of unknown risk, attending for their 11-week booking scan and 10 elevated-risk women attending for amniocentesis at the Aberdeen Maternity Hospital, Scotland.
  
  
  RESULTS
  Women value 'comprehensive' information of a full karyotype analysis at pounds 791, and 'simple' information of a rapid diagnostic test at pounds 690. Willingness to pay for a day's reduction in waiting time for results is pounds 18. Women prefer a prenatal service providing simple over comprehensive information as long as they receive results 6 days sooner than the comprehensive results would be provided.
  
  
  CONCLUSIONS
  While women prefer comprehensive information, the bulk of the value is placed on knowing whether the fetus has Down syndrome. Given the longer wait times for comprehensive information, simple information is preferred as long as results are received 6 days sooner than would be the case for comprehensive information. These results have implications for the resources dedicated to providing a rapid prenatal diagnostic service.
authors.affiliation: Health Economics Research Unit, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK. m.ryan@abdn.ac.uk
authors.forename: Mandy
authors.initials: M
authors.lastname: Ryan
authors.forename: Jane
authors.initials: J
authors.lastname: Diack
authors.forename: Verity
authors.initials: V
authors.lastname: Watson
authors.forename: Norman
authors.initials: N
authors.lastname: Smith
mesh_terms: D000293:Adolescent; D000328:Adult; D000649:Amniocentesis; D002869:Chromosome Aberrations / Q000196:embryology; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007621:Karyotyping / Q000379:methods*; D010342:Patient Acceptance of Health Care / Q000523:psychology*; D010865:Pilot Projects; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000191:economics; D011795:Surveys and Questionnaires; D013997:Time Factors