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Preliminary analysis of the new ‘Prenatal Risk Calculation (PRC)’ software

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Abstract

Objectives

In February 2007, the “Fetal Medicine Foundation Germany (FMF-D)” introduced its new calculation software for First Trimester Screening (FTS), called “Prenatal risk calculation (PRC)”. The aim of this study was to retrospectively investigate the test performance of PRC in comparison to the “NT module of the JOY software (JOY)”.

Methods

A total of 3,516 combined first trimester screenings from 11 + 0 to 13 + 6 weeks of gestation were accomplished according to the FMF-standard. Adjusted risk calculation for aneuploidy was performed with PRC and JOY.

Results

A total of 2,202 complete data sets of singleton pregnancies were analyzed, including 10 trisomy 21 cases, 4 trisomy 18 cases, and 1 trisomy 13 case. Risk calculation with PRC and JOY showed highly significant results (P value < 0.0001). JOY attained, at a cut-off of 1:300 (sensitivity 82.4%, false-positive rate 3.6%, positive predictive value 15.2%) and at a cut-off of 1:230 (82.4, 2.4, 21.2%), a better test performance in comparison to PRC (76.5, 7.1, 7.7% and 76.5, 5.3, 10.2%, respectively). The differences were highly significant (P value < 0.0001).

Conclusion

In this preliminary study, PRC demonstrated highly significant results in detecting aneuploidies in FTS. However, in comparison to JOY, its test performance was significantly inferior. A twice higher false positive rate would have doubled unnecessary invasive testing in a prospective setting. We therefore recommend a methodical revision of PRC.

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References

  1. Snijders RJM, Noble P, Sebire N, Souka A, Nicolaides KH (1998) UK multicentre project on assessment of risk of trisomy 21 by maternal age and fetal nuchal translucency thickness at 10–14 weeks of gestation. Fetal Medicine Foundation First Trimester Screening Group. Lancet 351:343–346

    Article  Google Scholar 

  2. Merz E (2002) 11–14 SSW Screening—Zertifizierte Ultraschalluntersuchung und zertifizierter biochemischer Test in der Frühgravidität. Ultraschall Med 23(3):161–162

    Article  PubMed  CAS  Google Scholar 

  3. Eiben B, Thode C, Glaubitz R, Merz E (2007) Das neue Ersttrimesterscreening-Programm PRC der FMF-Deutschland—Erste Erfahrungen zur Trisomie-21-Entdeckungsrate. Frauenarzt 48(5):468–470

    Google Scholar 

  4. Merz E (2007) First trimester screening—a new algorithm for risk calculation of chromosomal anomalies developed by FMF Germany. Ultraschall Med 28:270–272

    Article  PubMed  CAS  Google Scholar 

  5. Merz E, Thode C, Wellek S, Alkier A, Eiben B, Hackelöer BJ, Hansmann M, Huesgen G, Kozlowski P, Pruggmaier M (2007) Fetal Medicine Foundation Germany (FMF-D): a new approach to calculating the risk of chromosomal abnormalities with first-trimester screening data (11 + 1 to 14 + 0 weeks). Ultrasound Obstet Gynecol 30:542–543

    Article  Google Scholar 

  6. Schmidt P, Scharf A, Hörmansdörfer C, Elsässer M, Hillemanns P (2007) Unterschiedliche Berechnungsmethoden für das Ersttrimester Screening. Frauenarzt 48(11):1089–1092

    Google Scholar 

  7. Wald NJ, Hackshaw AK (1997) Combining ultrasound and biochemistry in first-trimester screening for Down’s syndrome. Prenat Diagn 17:821–829

    Article  PubMed  CAS  Google Scholar 

  8. Spencer K, Souter V, Tul N, Snijders R, Nicolaides KH (1999) Screening program for trisomy 21 at 10–14 weeks using fetal nuchal translucency, maternal serum free β-human chorionic gonadotropin an pregnancy-associated plasma protein-A. Ultrasound Obstet Gynecol 13:231–237

    Article  PubMed  CAS  Google Scholar 

  9. Schmidt P, Hörmansdörfer C, Hillemanns P, Scharf A (2008) Using Degree of Extremeness instead of Multiple of Median: an improved test strategy or just a gimmick in face of political motivations? Arch Gynecol Obstet 278(2):119–24

    Article  PubMed  CAS  Google Scholar 

  10. Schetinin V, Fieldsend JE, Partridge D, Coats TJ, Krzanowski WJ, Everson RM, Bailey TC, Hernandez A (2007) Confident interpretation of Bayesian decision tree ensembles for clinical applications. IEEE Trans Inf Technol Biomed 11(3):312–319

    Article  PubMed  Google Scholar 

  11. Palomaki GE, Haddow JE (1987) Maternal serum alpha-fetoprotein, age, and Down syndrome risk. Am J Obstet Gynecol 156(2):460–463

    PubMed  CAS  Google Scholar 

  12. Scharf A, Schmidt P, Seppelt M, Maul H, Wüstemann M, Sohn C (2003) Vergleich der Risikokalkulation für Trisomie 21 nach Nicolaides mit einer neu entwickelten Software: Retrospektive Analyse an 744 Fällen. Geburtshilfe Frauenheilkd 63:148–152

    Article  Google Scholar 

  13. Schmidt P, Staboulidou I, Soergel P, Wüstemann M, Hillemanns P, Scharf A (2007) Comparison of Nicolaides’ risk evaluation for Down’s syndrome with a novel software: an analysis of 1463 cases. Arch Gynecol Obstet 275:469–474

    Article  PubMed  Google Scholar 

  14. Scharf A (2003) Sohn C: Ein neues Konzept der Risikokalkulation beim Ersttrimester-Nackentransparenz-Test. Frauenarzt 44:289–291

    Google Scholar 

  15. Snijders RJ, Sebire NJ, Nicolaides KH (1995) Maternal age and gestational age-specific risk for chromosomal defects. Fetal Diagn Ther 10(6):356–367

    Article  PubMed  CAS  Google Scholar 

  16. Snijders RJ, Sundberg K, Holzgreve W, Henry G, Nicolaides KH (1999) Maternal age- and gestation-specific risk for trisomy 21. Ultrasound Obstet Gynecol 13(3):167–170

    Article  PubMed  CAS  Google Scholar 

  17. Nicolaides KH, Sebire N, Snijders RJM (1999) Nuchal translucency and chromosomal anomalies. In: Nicolaides KH, Sebire N, Snijders RJM (eds) The 11–14 week scan: the diagnosis of fetal abnormalities. Pathenon Publishing, Carnforth, pp 3–72

    Google Scholar 

  18. Wald NJ, Hackshaw AK (1997) Combining ultrasound and biochemistry in first-trimester screening for Down’s syndrome. Prenat Diagn 17(9):821–829

    Article  PubMed  CAS  Google Scholar 

  19. Schuchter K, Wald N, Hackshaw AK, Hafner E, Liebhart E (1998) The distribution of nuchal translucency at 10–13 weeks of pregnancy. Prenat Diagn 18:281–286

    Article  PubMed  CAS  Google Scholar 

  20. Yigiter AB, Kavak ZN, Bakirci N, Gokaslan H (2006) Effect of smoking on pregnancy-associated plasma protein A, free beta-human chorionic gonadotropin, and nuchal translucency in the first trimester of pregnancy. Adv Ther 23(1):131–138

    Article  PubMed  CAS  Google Scholar 

  21. Spencer K, Heath V, El-Sheikhah A, Ong CY, Nicolaides KH (2005) Ethnicity and the need for correction of biochemical and ultrasound markers of chromosomal anomalies in the first trimester: a study of Oriental, Asian and Afro-Caribbean populations. Prenat Diagn 25(5):365–369

    Article  PubMed  CAS  Google Scholar 

  22. Spencer K, Bindra R, Nicolaides KH (2003) Maternal weight correction of maternal serum PAPP-A and free beta-hCG MoM when screening for trisomy 21 in the first trimester of pregnancy. Prenat Diagn 23(10):851–855

    Article  PubMed  Google Scholar 

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Correspondence to Cindy Hörmansdörfer.

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Hörmansdörfer, C., Scharf, A., Golatta, M. et al. Preliminary analysis of the new ‘Prenatal Risk Calculation (PRC)’ software . Arch Gynecol Obstet 279, 511–515 (2009). https://doi.org/10.1007/s00404-008-0743-z

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  • DOI: https://doi.org/10.1007/s00404-008-0743-z

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