title: Trade-offs in prenatal detection of Down syndrome.
abstract: OBJECTIVE
  This paper presents the results of different screening policies for prenatal detection of Down syndrome that would allow decision makers to make informed choices.
  
  
  METHODS
  A decision analysis model was built to compare 8 screening policies with regard to a selected set of outcome measures. Probabilities used in the analysis were obtained from official administrative data reports in Spain and Catalonia and from data published in the medical literature. Sensitivity analyses were carried out to test the robustness of screening policies' results to changes in uptake rates, diagnostic accuracy, and resources consumed.
  
  
  RESULTS
  Selected screening policies posed major trades-offs regarding detection rates, false-positive results, fetal loss, and costs of the programs. All outcome measures considered were found quite robust to changes in uptake rates. Sensitivity and specificity rates of screening tests were shown to be the most influential factors in the outcome measures considered.
  
  
  CONCLUSIONS
  The disclosed trade-offs emphasize the need to comprehensively inform decision makers about both positive and negative consequences of adopting one screening policy or another.
authors.affiliation: Catalan Agency for Health Technology Assessment, Generalitat de Catalunya, Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Serra-Prat
authors.forename: P
authors.initials: P
authors.lastname: Gallo
authors.forename: A J
authors.initials: AJ
authors.lastname: Jovell
authors.forename: M
authors.initials: M
authors.lastname: Aymerich
authors.forename: M D
authors.initials: MD
authors.lastname: Estrada
mesh_terms: D000022:Abortion, Spontaneous / Q000209:etiology; D003663:Decision Trees; D004314:Down Syndrome / Q000517:prevention & control*; D005189:False Positive Reactions; D005260:Female; D006291:Health Policy; D006801:Humans; D008403:Mass Screening / Q000009:adverse effects / Q000191:economics / Q000379:methods*; D017063:Outcome Assessment, Health Care; D018579:Patient Selection; D011247:Pregnancy; D037841:Pregnant People; D011296:Prenatal Diagnosis / Q000009:adverse effects / Q000191:economics / Q000379:methods*; D011336:Probability; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012945:Social Values; D013030:Spain