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Related Experiment Video

Updated: Jun 29, 2026

A Machine Learning Approach to Design an Efficient Selective Screening of Mild Cognitive Impairment
12:18

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Down's syndrome screening: population statistic dependency of screening performance.

Tim Reynolds1, Guido Vranken, Jan Van Nueten

  • 1Queens Hospital Burton on Trent, Clinical Chemistry Department, Staffordshire, UK. tim.reynolds@burtonh-tr.wmids.nhs.uk

Clinical Chemistry and Laboratory Medicine
|October 8, 2008
PubMed
Summary

Optimizing Down's syndrome screening requires specific population data. Assay-specific settings for the triple test demonstrated superior efficacy in detecting Down's syndrome, highlighting the importance of tailored reference values.

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Area of Science:

  • Biochemistry
  • Genetics
  • Maternal-Fetal Medicine

Background:

  • Accurate Down's syndrome risk assessment relies on appropriate parameter sets.
  • Evaluating published population data against measurement procedure-specific parameters is crucial for optimizing screening efficacy.
  • This study analyzes samples to compare screening efficiency using different population data sets.

Purpose of the Study:

  • To evaluate the efficacy of different parameter sets for Down's syndrome risk calculation.
  • To compare screening efficiency using measurement procedure-specific parameters versus published population data.
  • To identify the optimal model for prenatal screening of Down's syndrome.

Main Methods:

  • Retrospective analysis of maternal serum samples from 286 unaffected and 95 Down's syndrome affected pregnancies.
  • Double and triple testing performed, with risk cut-off set at 1 in 250.
  • Receiver operating characteristics (ROC) curve analysis to estimate detection and false positive rates for various population settings.

Main Results:

  • Measurement procedure-specific settings yielded the highest triple test detection rate (77.9%) at a 5% false positive rate.
  • The triple test generally showed higher detection rates and a better area under the ROC curve compared to the double test.
  • Significant differences (p < 0.001) were observed in double and triple test risks across different models.

Conclusions:

  • The Beckman Coulter Access triple test, using assay-specific settings, meets performance standards for Down's syndrome screening.
  • Measurement procedure-specific reference values are essential for maximizing prenatal screening efficacy.
  • Availability of these specific reference values enhances the reliability of mid-trimester prenatal screening for Down's syndrome.