The Experts below are selected from a list of 10650 Experts worldwide ranked by ideXlab platform

Nicholas J Wald - One of the best experts on this subject based on the ideXlab platform.

Jonathan P Bestwick - One of the best experts on this subject based on the ideXlab platform.

  • Serum marker truncation limits in first trimester Antenatal Screening for trisomy 18.
    Journal of medical screening, 2018
    Co-Authors: Jonathan P Bestwick, Wayne J. Huttly, Nicholas J Wald
    Abstract:

    ObjectiveTo assess whether the accuracy of risk estimation in Antenatal Screening for trisomy 18 using the Combined test can be improved by revising the truncation limits of two serum markers.Metho...

  • Antenatal Screening for Down's syndrome, trisomy 18, and trisomy 13: Reporting a single Screening result for all three.
    Journal of medical screening, 2015
    Co-Authors: Jonathan P Bestwick, Nicholas J Wald
    Abstract:

    ObjectiveTo compare the performance of Antenatal Screening for Down’s syndrome (DS), trisomy 18 (T18), and trisomy 13 (T13) using a single risk of being affected by one of the three disorders, with...

  • Improvements in Antenatal Screening for Down's syndrome:
    Journal of medical screening, 2013
    Co-Authors: Nicholas J Wald, Jonathan P Bestwick, Wayne J. Huttly
    Abstract:

    ObjectivesTo estimate improvements to four Antenatal Screening tests for Down's syndrome (first trimester Combined, second trimester Quadruple, and first and second trimester Integrated and Serum Integrated tests) based on adding ductus venosus pulsatility index (DVPI), fetal nasal bone examination (NBE) and serum placental growth factor (PlGF).SettingStatistical analysis of data from several sources modelled using the maternal age distribution of live births in England and Wales from 2006 to 2008.MethodsMonte Carlo simulation carried out to estimate the Screening performance of tests with the addition of combinations of DVPI, NBE and PlGF.ResultsAt a 95% detection rate (DR), with first trimester markers measured at 11 completed weeks’ gestation, the addition of DVPI, NBE and PlGF decreased the false-positive rate (FPR) of the Combined test from 16.1% to 3.0%, the addition of PlGF to the Quadruple test decreased the FPR from 15.7% to 15.3%, the addition of DVPI, NBE and PlGF to the Integrated test decreas...

  • Antenatal Screening for Down Syndrome Using Serum Placental Growth Factor with the Combined, Quadruple, Serum Integrated and Integrated Tests
    PLOS ONE, 2012
    Co-Authors: Nicholas J Wald, L. George, Jonathan P Bestwick, Wayne J. Huttly
    Abstract:

    Objective To estimate the value of first or second trimester placental growth factor (PlGF) as an additional Antenatal Screening marker for Down syndrome.

  • Distribution of Nuchal Translucency in Antenatal Screening for Down's Syndrome:
    Journal of medical screening, 2010
    Co-Authors: Jonathan P Bestwick, Wayne J. Huttly, Nicholas J Wald
    Abstract:

    ObjectiveTo determine whether the standard deviation of nuchal translucency (NT) measurements has decreased over time and if so to revise the estimate and assess the effect of revising the estimate of the standard deviation on the performance of Antenatal Screening for Down's syndrome.SettingData from a routine Antenatal Screening programme for Down's syndrome comprising 106 affected and 22,640 unaffected pregnancies.MethodsNT measurements were converted into multiple of the median (MoM) values and standard deviations of log10 MoM values were calculated in affected and unaffected pregnancies. The Screening performance of the Combined and Integrated tests (that include NT measurement) were compared using previous and revised estimates of the standard deviation.ResultsThe standard deviation of NT in unaffected pregnancies has reduced over time (from 1998 to 2008) (e.g. from 0.1329 to 0.1105 [log10 MoM] at 12–13 completed weeks of pregnancy, reducing the variance by about 30%). This was not observed in affec...

Wayne J. Huttly - One of the best experts on this subject based on the ideXlab platform.

  • Antenatal Screening for down s syndrome revised nuchal translucency upper truncation limit due to improved precision of measurement
    Journal of Medical Screening, 2020
    Co-Authors: Stephen H Vale, Wayne J. Huttly, Nicholas J Wald
    Abstract:

    ObjectiveTo 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 mul...

  • Serum marker truncation limits in first trimester Antenatal Screening for trisomy 18.
    Journal of medical screening, 2018
    Co-Authors: Jonathan P Bestwick, Wayne J. Huttly, Nicholas J Wald
    Abstract:

    ObjectiveTo assess whether the accuracy of risk estimation in Antenatal Screening for trisomy 18 using the Combined test can be improved by revising the truncation limits of two serum markers.Metho...

  • Improvements in Antenatal Screening for Down's syndrome:
    Journal of medical screening, 2013
    Co-Authors: Nicholas J Wald, Jonathan P Bestwick, Wayne J. Huttly
    Abstract:

    ObjectivesTo estimate improvements to four Antenatal Screening tests for Down's syndrome (first trimester Combined, second trimester Quadruple, and first and second trimester Integrated and Serum Integrated tests) based on adding ductus venosus pulsatility index (DVPI), fetal nasal bone examination (NBE) and serum placental growth factor (PlGF).SettingStatistical analysis of data from several sources modelled using the maternal age distribution of live births in England and Wales from 2006 to 2008.MethodsMonte Carlo simulation carried out to estimate the Screening performance of tests with the addition of combinations of DVPI, NBE and PlGF.ResultsAt a 95% detection rate (DR), with first trimester markers measured at 11 completed weeks’ gestation, the addition of DVPI, NBE and PlGF decreased the false-positive rate (FPR) of the Combined test from 16.1% to 3.0%, the addition of PlGF to the Quadruple test decreased the FPR from 15.7% to 15.3%, the addition of DVPI, NBE and PlGF to the Integrated test decreas...

  • Antenatal Screening for Down Syndrome Using Serum Placental Growth Factor with the Combined, Quadruple, Serum Integrated and Integrated Tests
    PLOS ONE, 2012
    Co-Authors: Nicholas J Wald, L. George, Jonathan P Bestwick, Wayne J. Huttly
    Abstract:

    Objective To estimate the value of first or second trimester placental growth factor (PlGF) as an additional Antenatal Screening marker for Down syndrome.

  • Distribution of Nuchal Translucency in Antenatal Screening for Down's Syndrome:
    Journal of medical screening, 2010
    Co-Authors: Jonathan P Bestwick, Wayne J. Huttly, Nicholas J Wald
    Abstract:

    ObjectiveTo determine whether the standard deviation of nuchal translucency (NT) measurements has decreased over time and if so to revise the estimate and assess the effect of revising the estimate of the standard deviation on the performance of Antenatal Screening for Down's syndrome.SettingData from a routine Antenatal Screening programme for Down's syndrome comprising 106 affected and 22,640 unaffected pregnancies.MethodsNT measurements were converted into multiple of the median (MoM) values and standard deviations of log10 MoM values were calculated in affected and unaffected pregnancies. The Screening performance of the Combined and Integrated tests (that include NT measurement) were compared using previous and revised estimates of the standard deviation.ResultsThe standard deviation of NT in unaffected pregnancies has reduced over time (from 1998 to 2008) (e.g. from 0.1329 to 0.1105 [log10 MoM] at 12–13 completed weeks of pregnancy, reducing the variance by about 30%). This was not observed in affec...

Judith Searle - One of the best experts on this subject based on the ideXlab platform.

  • Routine Antenatal Screening: not a case of informed choice.
    Australian and New Zealand journal of public health, 1997
    Co-Authors: Judith Searle
    Abstract:

    : Traditional epidemiological criteria are inadequate for comprehensively evaluating Screening activities to identify best practice. In 1995, a study of women in the postnatal period at a major metropolitan teaching hospital in Victoria was conducted to assess, through their perspectives, the role of other factors of significance for the evaluation of routine Antenatal Screening. In particular, the role of informed choice was examined. The study involved a survey of 376 women and 21 semistructured interviews. The study found that, with an ‘opt—out’ or routine system of Screening, high rates of use were achieved at the expense of informed choice for some participants. In addition, disturbing differences in information delivery and information perception were found between public and private patients. The need for new criteria to identify what constitutes best practice in the delivery of Antenatal Screening programs is discussed. These criteria should incorporate consideration of broader social and ethical implications for women receiving Antenatal Screening.

Susan Petit - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of universal Antenatal Screening for group b streptococcus
    The New England Journal of Medicine, 2009
    Co-Authors: Melissa K. Van Dyke, Christina R. Phares, Ruth Lynfield, Ann Thomas, Kathryn E. Arnold, Allen S. Craig, Ken Gershman, William Schaffner, Janet C Mohleboetani, Susan Petit
    Abstract:

    Background Group B streptococcal disease is one of the most common infections in the first week after birth. In 2002, national guidelines recommended universal late Antenatal Screening of pregnant women for colonization with group B streptococcus to identify candidates for intrapartum chemoprophylaxis. Methods We evaluated the implementation of the guidelines in a multistate, retrospective cohort selected from the Active Bacterial Core surveillance, a 10-state, population-based system that monitors invasive group B streptococcal disease. We abstracted data from the labor and delivery records of a stratified random sample of live births and of all cases in which the newborn had early-onset group B streptococcal disease (i.e., disease in infants <7 days of age) in 2003 and 2004. We compared our results with those from a study with a similar design that evaluated Screening practices in 1998 and 1999. Results We abstracted records of 254 births in which the infant had group B streptococcal disease and 7437 bi...

  • Evaluation of Universal Antenatal Screening for Group B Streptococcus
    Obstetrical & Gynecological Survey, 2009
    Co-Authors: Melissa K. Van Dyke, Christina R. Phares, Ruth Lynfield, Ann Thomas, Kathryn E. Arnold, Allen S. Craig, Janet C. Mohle-boetani, Ken Gershman, William Schaffner, Susan Petit
    Abstract:

    ABSTRACTIn 2002, updated national guidelines recommended universal culture-based Antenatal Screening of pregnant women during labor and delivery for detection of colonization with group B streptococcus. Four years later, a population-based surveillance study reported a 27% decrease in incidence of e