Reproducibility of Risk Figures in 2nd-Trimester Maternal Serum Screening for Down Syndrome: Comparison of 2 Laboratories

Benn, Peter; Makowski, Gregory S.; Egan, James; Wright, Dave

doi:10.1373/clinchem.2006.068783

Cited by 7 publications

(8 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Serum screening has shown to be cost-effective for detecting Down syndrome (23 ) and can reduce the need for invasive amniocentesis (24,25 ). However, recent studies revealed poor accuracy and imprecision of RIA in measuring uE 3 compared with results obtained from liquid chromatographytandem mass spectrometry (LC-MS/MS) analyses, and poor agreement of uE 3 concentrations was observed between RIA and chemiluminescent immunoassay methods (26,27 ). More importantly, discrepancies in assay performance of various kits that cannot be normalized by applying multiples of the median (MoMs) could impact the accuracy of the risk estimation for Down syndrome (27)(28)(29)(30).…”

mentioning

confidence: 99%

“…However, recent studies revealed poor accuracy and imprecision of RIA in measuring uE 3 compared with results obtained from liquid chromatographytandem mass spectrometry (LC-MS/MS) analyses, and poor agreement of uE 3 concentrations was observed between RIA and chemiluminescent immunoassay methods (26,27 ). More importantly, discrepancies in assay performance of various kits that cannot be normalized by applying multiples of the median (MoMs) could impact the accuracy of the risk estimation for Down syndrome (27)(28)(29)(30). Concerns regarding poor accuracy of RIA, EIA, or ELISA methods in uE 3 testing have also been raised in the fields of epidemiology and breast cancer risk assessment (17,31 ).…”

mentioning

confidence: 99%

“…Since 2000, chemiluminescent immunoassays have become commonly used in clinical laboratories in the US for uE 3 testing (26,27 ). This methodology has advantages over other immunoassays in that it is analytically more sensitive and testing can be carried out on an automated analyzer, therefore reducing human error.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

et al. 2014

View full text Add to dashboard Cite

BACKGROUND Unconjugated estriol (uE3) is routinely analyzed in clinical laboratories as risk assessment for Down syndrome. Immunoassays of various types are the most commonly used methods. The accuracies of RIAs and ELISAs for uE3 have been questioned, and to date there have been no independent studies investigating the accuracy of the relatively new chemiluminescent immunoassays. We developed and validated a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for uE3 measurements in serum. METHODS Serum samples from patients in the second trimester of pregnancy were used, and uE3 concentrations were measured by LC-MS/MS and the Beckman Coulter Access® 2 and Siemens IMMULITE 2000 automatic chemiluminescent immunoassay analyzers. RESULTS The LC-MS/MS method was validated and showed limit of detection 0.05 ng/mL; limit of quantification 0.2 ng/mL; linearity of response to 32 ng/mL; total imprecision of 16.2%, 10.4%, and 8.2% for uE3 at 1.10, 4.18, and 8.32 ng/mL, respectively; and analytical recoveries of 95.9%–104.2%. ANOVA of the correlation for LC-MS/MS results vs chemiluminescent immunoassays results showed R2 = 0.9678 (Access 2 = 0.9305 LC-MS/MS + 0.2177, Sy|x = 0.1786, P < 0.0001), and R2 = 0.9663 (IMMULITE 2000 = 0.8849 LC-MS/MS − 0.0403, Sy|x = 0.1738, P < 0.0001). Bland–Altman plots of uE3 results revealed concentration-dependent immunoassay biases. Mock risk analysis for Down syndrome showed no apparent difference in the risk assessment outcomes if the adjusted method-specific multiples of the median were used, and the assay imprecision was <10% CV. CONCLUSIONS Standardization of immunoassay methods for uE3 analysis is needed to improve the accuracy of the measurements.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Yapılan bir çalışmada farklı iki laboratuvar da aynı serum çalışılmış fakat sonuçlar istatistiksel olarak ileri düzey-de anlamlı bulunmuştur. Aradaki farkın laboratuvarlarda kullanılan yöntem farklılığından kaynaklandığı ifade edilmiştir [20].…”

Section: Discussionunclassified

Determınatıon Of The Medıan Values Of Trıple Test Screening Parametres İn Yozgat Regıon

Akarsu¹

2014

Turk J Bioch

View full text Add to dashboard Cite

Objective: In this study our purpose was to determine the median values of the triple test screening parameters in Yozgat region and to compare with new calculated median values being used to SsdwLab 5 median values. Methods: The study retrospectively investigated alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (β-HCG) and unconjugated estriol (uE3) values among 721 pregnant women who visited to Biochemical Laboratory of Yozgat Bozok Maternity and Children's Diseases Hospital in order to have triple screening test between 2011 and 2012 and whose gestational ages were between 14th and 18th week. All parameters were recalculated according to14-18. weeks. The compared with new calculated median values to SsdwLab 5 median values. Results: As a result; it was found out that the newly calculated median β hCG values in the 15th week were significantly higher than median β-HCG values in the program whereas median β hCG values in the 17th and 18th week were significantly lower than median β-HCG values in the program (p<0.05). The newly calculated median AFP values in the 15th week were significantly higher than median AFP values in the program (p<0.05). The newly calculated median uE3 values in the 16th, 17th and 18th weeks were significantly lower than median uE3 values in the program (p<0.05). Conclusion: Instead of the use of the median values already entered in the program during the prenatal risk assessment; the use of median values specific to each province may contribute to the reliability of triple screening tests, to a more accurate calculation of prenatal risks and to prevention of unnecessary invasive tests used for mother and fetus. Tüm parametreler 14-18. haftalara göre yeniden hesaplanmıştır. Yeni hesaplanan medyan değerleri SsdwLab 5 medyan değerleri ile karşılaştırılmıştır. Bulgular: Yeni hesaplanan 15. hafta β-HCG medyan değeri, programdaki β-HCG medyan değerinden anlamlı derecede yüksek, 17, 18. hafta β hCG medyan değerleri, programdaki β hCG medyan değerlerinden anlamlı derecede düşük bulunmuştur (p<0.05). Yeni hesaplanan 15. hafta AFP medyan değeri, programdaki AFP medyan değerinden anlamlı derecede yüksek (p<0.05) bulunmuştur. Yeni hesaplanan 16, 17, 18. hafta uE3 medyan değerleri, programdaki uE3 medyan değerlerinden anlamlı derecede düşük bulunmuştur (p<0.05). Sonuç: Prenatal risk değerlendirmesi sırasında kullanılmakta olan programlara girilmiş medyan değerleri yerine, bölgelere ait medyan değerlerinin kullanılması üçlü tarama tarama testlerinin güvenilirliğini arttırmasına, prenatal risklerin daha doğru hesaplamasına, anne ve fetüsün gereksiz yere invaziv testlere maruziyetinin azaltılmasına katkı sağlayabilir. Anahtar Kelimeler: Üçlü tarama testi, bölgesel medyan, prenatal tanı Çıkar Çatışması: Yazarların çıkar çatışması yoktur.

show abstract

“…3,4,14 This study both assessed stabilization of samples and evaluated variations due to using different Instruments.…”

Section: Figurementioning

confidence: 99%

The Affect of Different Immunoassay Systems and Preanalytical Variables on Second Trimester Aneuploidy Screening Test Results

Öztürk¹,

Ozturk²,

Güçel³

et al. 2016

Turkiye Klinikleri J Med Sci

View full text Add to dashboard Cite

A AB BS ST TR RA AC CT T O Ob bj je ec ct ti iv ve e: : Triple test is a screening test used in prenatal diagnosis of the disease that chromosomal defects such as Trisomy 18, 21 (Down syndrome) and neural tube defects (NTD). The objective of this study was to investigate the effects of sample storage conditions and different instruments on triple test individual risk results. M Ma at te er ri ia al l a an nd d M Me et th ho od ds s: : Serum samples were divided into four aliquots to measure alpha fetoprotein (AFP), beta human chorionic gonadotropin (β-hCG) and unconjugated Estriol (uE3). The one group of samples were measured on the same day, the other samples were then kept in the refrigerator (+4°C) and measured at Day 2 and at Day 7, in the deep freezer (-20°C) at Day 7 respectively. Each sample was individually measured in Beckman DXI 800 (Instrument 1) and Siemens IMMULITE 2000 (Instrument 2) Instruments, and MoM values and patient's individual risks were calculated for AFP, β-hCG and uE3 tests using PRA (Prenatal Risk Calculation, Benetech Software, Toronto) and PRISCA 4.0 (Prenatal Risk Calculation, TYPOLOG Software/GmBH, Hamburg, Germany) programs respectively. R Re es su ul lt ts s: : The difference between AFP MoM values was observed for the 1 st and 2 nd day of the 1st instrument (p <0.05). In comparison of day 1 st and 7 th day of measurement results differences were observed for AFP and β-hCG at +4°C and AFP and uE3 MoM values at -20°C. (p<0.05). The difference between AFP MoM values was observed for the 1 st and 2 nd day of the 2 nd instrument (p<0.05). When 1 st and 7 th day measurement results were compared, it was seen that there was a difference in uE3 and β-hCG MoM values in both the +4°C and -20°C pending samples (p<0.05). There was a significant difference (p<0.05) in MoM values of two Instruments, obtained from β-HCG, uE3 and AFP tests. Despite a significant difference in analytical variation, no significant differences were found between 2 instruments after evaluating patient's individual risks (p=0.58, p=0.59, p=0.33, p=0.65). C Co on nc cl lu us si io on n: : Waiting time for samples is a preanalytical variable that influences the individual risk results from triple test. For Down Syndrome, it is considered that different analytical performances have no effects on individual risk for patients whose individual risk is not near the limit value.

show abstract

Reproducibility of Risk Figures in 2nd-Trimester Maternal Serum Screening for Down Syndrome: Comparison of 2 Laboratories

Cited by 7 publications

References 21 publications

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

Determınatıon Of The Medıan Values Of Trıple Test Screening Parametres İn Yozgat Regıon

The Affect of Different Immunoassay Systems and Preanalytical Variables on Second Trimester Aneuploidy Screening Test Results

Contact Info

Product

Resources

About