title: Comparison of risk calculation approaches in a screening programme for Down syndrome.
abstract: In the Netherlands, both the LifeCycle Elipse (LC) and the Astraia software package are used to calculate the risk of having a child with Down syndrome. Therefore, pregnant women can be presented with dissimilar risks. In this study the conformity between these risks before and after harmonization of the screening program and its influence on the performance indicators of the first trimester screening were evaluated. The agreement between combined risks (based on the biochemical parameters PAPP-A and fβ-hCG and a nuchal translucency measurement) was expressed as intraclass correlation coefficient (ICC)=0.99. Conformity between combined risks was better after harmonization (Cohen's κ=0.75) than before harmonization (Cohen's κ=0.63). For both risk calculation software packages the area under the ROC-curve was 0.84. The database contained 42 Down syndrome cases; based on the odds of being affected given a positive result (OAPR), LC performed slightly better than Astraia before harmonization (17.9 vs. 21.5, respectively). It has been acknowledged that using different software packages could lead to dissimilar risk calculations. In this study the screening performance indicators of two software packages were quite similar. The agreement of the screening performance after harmonization remains to be seen, but is expected to be even higher.
authors.affiliation: Laboratory for Infectious Diseases and Screening, National Institute for Public Health and the Environment, Bilthoven, The Netherlands.
authors.forename: Maria P H
authors.initials: MP
authors.lastname: Koster
authors.forename: Kirsten M
authors.initials: KM
authors.lastname: Heetkamp
authors.forename: Esteriek
authors.initials: E
authors.lastname: de Miranda
authors.forename: Peter C J I
authors.initials: PC
authors.lastname: Schielen
mesh_terms: D000293:Adolescent; D000328:Adult; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D004314:Down Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D048208:Nuchal Translucency Measurement; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism; D011296:Prenatal Diagnosis / Q000379:methods* / Q000706:statistics & numerical data; D012306:Risk; D012307:Risk Factors; D012984:Software; D055815:Young Adult
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human; D011266:Pregnancy-Associated Plasma Protein-A