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The article focuses on study of financial analysis is carried out to assess costs and benefits of providing cell-free DNA screening in Finland, using different strategies. Topics discussed include considering the place of cell-free DNA screening it is important to make explicit the additional and marginal costs of different screening strategies and the associated benefits; and most assumptions the balance is favorable for Contingent screening.

Background: We developed a decision aid (DA) to help pregnant women and their partners make informed decisions about prenatal screening for trisomy. We aimed to determine its usefulness for preparing for decision-making and its acceptability among end-users.Methods: In this mixed-methods pilot study, we recruited participants in three prenatal care settings in Quebec City. Eligible women were over 18 and more than 16 weeks pregnant or had given birth recently. We asked them about the usefulness of the DA using an interview grid based on the Technology Acceptance Model. We performed descriptive statistics and deductive analysis.Results: Thirty-nine dyads or individuals participated in the study. Mean usefulness score was 86.2 ± 13. Most participants found the amount of information in the DA just right (79.5%), balanced (89.7%), and very useful (61.5%). They were less satisfied with the presentation and the values worksheet and suggested different values clarification methods.Conclusion: Rigorous pilot tests of DAs with patients are an important stage in their development before the more formal assessments that precede scaling up the DA in clinical practice.Practice Implications: The next version of the DA will integrate the suggestions of end-users for better decision-making processes about prenatal screening for trisomy. [ABSTRACT FROM AUTHOR]

Objective: To determine whether the improved precision of nuchal translucency (NT) measurement used in antenatal screening for Down's syndrome observed over time as evidenced by a decrease in the multiple of the median (MoM) standard deviation requires a modification to the NT MoM truncation limits to maintain accurate risk estimation. Methods: Probability plots were derived from the measurements of NT MoM values used in a 2018 audit of 22,362 unaffected pregnancies. The plots were used to determine whether the NT MoM upper truncation limit should be lowered. Validation plots were used to assess the screening accuracy of Down's syndrome risk estimates calculated from observed NT MoM values in the 22,362 unaffected pregnancies and 69 Down's syndrome pregnancies for original and revised NT MoM truncation limits. Results: Probability plots indicated that with improved precision of NT measurements, there was deviation from a Gaussian distribution at less high MoM values than with less precise measurements. Validation plots showed that using the current NT MoM upper truncation limit of 2.5 MoM with improved precision NT measurements overestimates the Down's syndrome risk (median risk in highest risk category expressed as an odds was 53.3:1 and observed prevalence was 1:1.1). The large discrepancy was corrected by changing the NTupper truncation limit to 2.0 MoM (median risk in highest risk category expressed as an odds was 1:1.78 and observed prevalence 1:2.7). Conclusion: The NT MoM upper truncation limit should be reduced from 2.5 to 2.0 MoM. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study is to identify the optimal cut-off points of contingent serum screening excluding nuchal translucency (NT) measurement, to categorize the risk level in the first trimester.Methods: A prospective database of women undergoing contingent serum screening, without NT measurement, was reviewed. In conventional categorization, the results of first-trimester screening were categorized into high risk (>1:30) (invasive diagnosis was offered); intermediate risk (1:30-1:1500) (second-trimester screening was needed); and low risk (<1:1500) (no further test). We recategorized the risk levels using various upper and lower cut-offs and compared detection rates, false-positive rates, and rates of intermediate risk.Results: Among 24,874 women, the prevalence of Down syndrome was 1:691. The previously agreed cut-offs had a detection rate of 88.9% and a false-positive rate of 8.5% with high rate of intermediate risk (38.2%). Re-categorization provided the optimal lower and upper cut-offs 1/900 and 1/50, respectively, giving a detection rate of 86.1%, a false-positive rate of 8.1%, and a rate of intermediate risk of 24.8%.Conclusions: This is the first study on contingent serum screening without NT measurement which shows a high detection rate with an acceptable false-positive rate. The optimal cut-offs to categorize the risk levels of the upper and the lower cut-off was 1:30-1:50 and 1:900, respectively. [ABSTRACT FROM AUTHOR]

Objectives: To examine the costs and outcomes of different screening strategies for Down Syndrome (DS) in singleton pregnancies.Study Design: A decision-analytic model was developed to compare the costs and the outcomes of different prenatal screening strategies. Five strategies were compared for women under 35-year of age: 1A) triple test (TT), 2A); combined test (CT), 3A) Non-invasive Prenatal Screening Test by using cell free fetal DNA (NIPT), 4A) and 5A) NIPT as a second-step screening for high-risk patients detected by either TT, or CT respectively. For women ≥35-year of age, 1B) implementing invasive test (amniocentesis -AC) and 2B) NIPT for all women were compared. Data was analyzed to obtain the outcomes, total costs, the cost per women and the incremental cost-effectiveness ratios (ICERs) for screening strategies.Results: Among the current strategies for women under 35 years old, CT is clearly dominated to TT, as it is more effective and less costly. Although, the current routine practice (2A) is the least-costly strategy, implementing NIPT as a second step screening to high-risk women identified by CT (5A) would be more effective than 2A; leading to a 10.2% increase in the number of detected DS cases and a 96.3% reduction in procedural related losses (PRL). However, its cost to the Social Security Institution that is a public entity would be 17 times higher and increase screening costs by 1.5 times. Strategy 5A would result in an incremental cost effectiveness of 6,873,082 (PPP) US$ when compared to the current one (2A). Strategy 1B-for offering AC to all women ≥35-year of age is dominated over NIPT (2B), as it would detect more DS cases and would be less costly. On the other hand, there would be 206 PRL associated with AC, but NIPT provides clear clinical benefits as there would be no PRL with NIPT.Conclusions: NIPT leads to very high costs despite its high effectiveness in terms of detecting DS cases and avoiding PRL. The cost of NIPT should be decreased, otherwise, only individuals who can afford to pay from out-of-pocket could benefit. We believe that reliable cost-effective prenatal screening policies are essential in countries with low and smiddle income and high birth rates as well. [ABSTRACT FROM AUTHOR]

Background Contingent screening for trisomy 21 using non-invasive prenatal testing has the potential to reduce invasive diagnostic testing and increase the detection of trisomy 21. Aim To describe the diagnostic and economic performance of prenatal screening models for trisomy 21 that use non-invasive prenatal testing as a contingent screen across a range of combined first trimester screening risk cut-offs from a public health system perspective. Methods Using a hypothetical cohort of 300 000 pregnancies, we modelled the outcomes of 25 contingent non-invasive prenatal testing screening models and compared these to conventional screening, offering women with a high-risk (1 > 300) combined first trimester screening result an invasive test. The 25 models used a range of risk cut-offs. High-risk women were offered invasive testing. Intermediate-risk women were offered non-invasive prenatal testing. We report the cost of each model, detection rate, costs per diagnosis, invasive tests per diagnosis and the number of fetal losses per diagnosis. Results The cost per prenatal diagnosis of trisomy 21 using the conventional model was $51 876 compared to the contingent models which varied from $49 309-66 686. The number of diagnoses and cost per diagnosis increased as the intermediate-risk threshold was lowered. Results were sensitive to trisomy 21 incidence, uptake of testing and cost of non-invasive prenatal testing. Conclusion Contingent non-invasive prenatal testing models using more sensitive combined first trimester screening risk cut-offs than conventional screening improved the detection rate of trisomy 21, reduced procedure-related fetal loss and could potentially be provided at a lower cost per diagnosis than conventional screening. [ABSTRACT FROM AUTHOR]

Objective: To evaluate first-trimester screening protocols for detecting trisomy 21 in an Indian population.Methods: The present prospective study collected data from women with singleton pregnancies and a crown-to-rump length of 45-84 mm who presented at the fetal medicine unit of a tertiary care center in North India between June 1, 2006, and December 31, 2015, for combined first-trimester screening. Maternal age, nuchal translucency, nasal bone, and maternal serum levels of free beta human chorionic gonadotropin and pregnancy-associated plasma protein A were assessed for calculating the risk of trisomy 21. Tricuspid regurgitation and qualitative analysis of ductus venosus data were available from June 2010, and were included where available. Trisomy-21 detection rates were calculated for various screening protocols and were compared.Results: There were 4523 women screened and 24 records of trisomy 21. Combined screening with maternal age, nuchal translucency, nasal bone, tricuspid regurgitation, and ductus venosus demonstrated optimal detection and false-positive rates of 93.8% and 1.9%, respectively. Screening using only maternal age yielded a detection rate of 37.5%; using fixed nuchal translucency cut-off values of 2.5 and 3 mm resulted in detection rates of 66.7% and 37.5%, respectively.Conclusion: Combined first-trimester screening performed well in an Indian population; combining maternal age, nuchal translucency, nasal bone, ductus venosus, and tricuspid regurgitation yielded the most accurate screening. [ABSTRACT FROM AUTHOR]

Background: Health professionals are expected to engage pregnant women in shared decision making to help them make informed values-based decisions about prenatal screening. Patient decision aids (PtDAs) foster shared decision-making, but are rarely used in this context. Our objective was to identify factors that could influence health professionals to use a PtDA for decisions about prenatal screening for Down syndrome during a clinical pregnancy follow-up.Methods: We planned to recruit a purposive sample of 45 health professionals (obstetrician-gynecologists, family physicians and midwives) involved in the care of pregnant women in three clinical sites (15 per site). Participating health professionals first watched a video showing two simulated consecutive prenatal follow-up consultations during which a pregnant woman, her partner and a health professional used a PtDA about Down syndrome prenatal screening. Participants were then interviewed about factors that would influence their use of the PtDA. Questions were based on the Theoretical Domains Framework. We performed content analyses of transcribed verbatim interviews.Results: Out of 42 eligible health professionals approached, 36 agreed to be interviewed (86 % response rate). Of these, 27 were female (75 %), nine were obstetrician-gynecologists (25 %), 15 were family physicians (42 %), and 12 were midwives (33 %), with a mean age of 42.1 ± 11.6 years old. We identified 35 distinct factors reported by 20 % or more participants that were mapped onto 10 of the 12 of the Theoretical Domains Framework domains. The six most frequently mentioned factors influencing use of the PtDA were: 1) a positive appraisal (n = 29, 81 %, beliefs about consequences domain); 2) its availability in the office (n = 27, 75 %, environmental context and resources domain); 3) colleagues' approval (n = 27, 75 %, social influences domain); 4) time constraints (n = 26, 72 %, environmental context and resources domain); 5) finding it a relevant source of information (n = 24, 67 %, motivation and goals domain); and 6) not knowing any PtDAs (n = 23, 64 %, knowledge domain).Conclusions: Appraisal, PtDA availability, peer approval, time concerns, evidence and PtDA awareness all affect whether health professionals are likely to use a PtDA to help pregnant women make informed decision about Down syndrome screening. Implementation strategies will need to address these factors. [ABSTRACT FROM AUTHOR]

Objective: To analyse population-based trends over the entire history of prenatal testing for aneuploidy.Design: Retrospective analysis of state-wide data sets.Setting: Australian state of Victoria with ~70 000 annual births.Population: All pregnant women undergoing invasive prenatal testing at <25 weeks' gestation from 1976 to 2013.Methods: Analysis of three state-wide data sets: (1) Prenatal diagnosis data set of 119 404 amniocenteses and chorionic villus samplings from 1976 to 2013; (2) central serum screening laboratory data set from 1996 to 2013; (3) government birth statistics from 1976 to 2013.Main Outcome Measures: Annual numbers and uptake rates of invasive prenatal tests and serum screening, indications for invasive prenatal testing, prenatal diagnoses of aneuploidy, diagnostic yield of invasive tests.Results: Annual numbers of invasive prenatal tests climbed steadily from 1976, then declined from 2000. In 2013, the number of invasive prenatal tests was the lowest in 25 years, while the number of trisomy 21 diagnoses was the highest ever recorded. Annual uptake of serum screening climbed from 1.6 to 83% over 1996-2013. Results from 2013 showed a high diagnostic yield (15.8%) for a low rate of invasive testing (3.4% of births). Over four decades, the number of invasive procedures performed for each diagnosis of major chromosome abnormality declined from 100 to six.Conclusions: This study demonstrates historic reductions in the proportion of women undergoing invasive testing and dramatic improvements in diagnostic yield. Monitoring the impact of new prenatal technologies on this progress remains an important research priority.Tweetable Abstract: Invasive prenatal testing has reached historic lows due to dramatic improvements in Down syndrome screening. [ABSTRACT FROM AUTHOR]

Objective: To report the strategy of first-trimester aneuploidy screening in pregnancies at risk for homozygous α(0)-thalassemian.Methods: Women at risk of homozygous α(0)-thalassemia were given an ultrasound examination at 11-14 weeks' gestation to exclude an affected pregnancy. Fetal cardiothoracic ratio (CTR) and nuchal translucence (NT) were measured. If cardiomegaly was found, chorionic villus sampling (CVS) was offered for α-thalassemia; otherwise the first-trimester combined screening test was performed on the pregnancy. The invasive testing for karyotyping was only followed in those cases with a positive aneuploidy screening test.Results: In total, 69 of 288 pregnancies were found to be affected by homozygous α(0)-thalassemia using ultrasound, and the findings were confirmed by invasive testing. In the remaining 219 pregnancies, invasive testing was not performed for α-thalassemia because of a normal fetal CTR, and the women received the first-trimester combined screening. Nine CVS procedures were performed for karyotyping because of a positive aneuploidy screening. Totally three pregnancies with aneuploidy were diagnosed and terminated.Conclusions: Our strategy can selectively detect aneuploidy pregnancies not affected by homozygous α-thalassemia, and, meanwhile, save on the cost of unnecessary aneuploidy screening or karyotyping in pregnancies with an affected fetus of homozygous α(0)-thalassemia. [ABSTRACT FROM AUTHOR]

Pregnancy-associated plasma protein A (PAPP-A) is a maternal serum marker of fetal chromosomal disease and a risk marker for adverse outcome. PAPP-A in the circulation exists both as a 2:2 complex (PAPP-A/proMBP) with the proform of eosinophil major basic protein (proMBP) and as dimeric PAPP-A. Non-PAPP-A containing proMBP complexes constitute the bulk of proMBP in maternal serum. We developed and characterized a sandwich enzyme immunoassay for PAPP-A using a polyclonal rabbit anti-PAPP-A/proMBP antibody (SSI 6823) and a monoclonal murine anti-PAPP-A/proMBP antibody (HYB 234-3), reactive with the PAPP-A part of PAPP-A/proMBP. The assay range was 2 mIU/L-500 mIU/L, intra- and inter-assay coefficients of variation <10%. The immunoreactivity eluted ahead of thyroglobulin, Mr 669 kDa, in gel filtration and bound to a heparin column. Serum concentrations of PAPP-A were determined in gestational weeks 5-13 in 167 pregnant women with normal fetuses and 39 women with Down's syndrome (DS) fetuses. The median PAPP-A MoM (multiples of the median in normal controls) in DS pregnancies was 0.30 (quartile range: 0.17-0.54). The PAPP-A logMoMs in DS pregnancies were normally distributed with a mean of -0.5927 and SD of 0.3639. When simulating the performance of PAPP-A and age as markers for DS in population screening a detection rate (DR) of 62% was found for a screen positive rate (SPR) of 5%. Together with beta-HCG and nuchal translucency, two other first trimester markers for fetal DS, a DR 90% could be obtained for an SPR of 5%. [ABSTRACT FROM AUTHOR]

Objective: We analyzed the cost-effectiveness (CE) and performances of commonly used prenatal Down syndrome (DS) screening strategies. Study Design: We performed computer simulations to compare 8 screening options by applying empirical data from Serum, Urine, and Ultrasound Screening Study trials on the population of 110,948 pregnancies. Screening strategies outcomes, CE ratios, and incremental CE ratios were measured. Results: The most CE DS screening strategy was the contingent screening method (CE ratio of Can$26,833 per DS case). Its incremental CE ratio compared to the second-most CE strategy (serum integrated screening) was Can$3815 per DS birth detected. Among the procedures respecting guidelines, our results identified the combined test as the screening strategy with the highest CE ratio (Can$47,358) and the highest number of procedure-related euploid miscarriages (n = 71). Conclusion: In regard to CE, contingent screening is the best choice. The combined test, which is the most popular screening strategy, shows many limitations. [ABSTRACT FROM AUTHOR]