eprintid: 10127016
rev_number: 16
eprint_status: archive
userid: 608
dir: disk0/10/12/70/16
datestamp: 2021-05-05 16:30:32
lastmod: 2022-01-12 23:56:27
status_changed: 2021-05-05 16:30:32
type: article
metadata_visibility: show
creators_name: Vale, SH
creators_name: Huttly, WJ
creators_name: Wald, NJ
title: Antenatal screening for Down’s syndrome: Revised nuchal translucency upper truncation limit due to improved precision of measurement
ispublished: inpress
divisions: UCL
divisions: B02
divisions: DD4
note: This article is distributed under the terms of the Creative Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/) which permits any use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).
abstract: 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 NT upper 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.
date: 2020-07-01
date_type: published
official_url: https://doi.org/10.1177/0969141320937321
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 1832970
doi: 10.1177/0969141320937321
lyricists_name: Wald, Nicholas
lyricists_id: NJWAL52
actors_name: Zahnhausen-Stuber, Petra
actors_id: PMZAH20
actors_role: owner
full_text_status: public
publication: Journal of Medical Screening
citation:        Vale, SH;    Huttly, WJ;    Wald, NJ;      (2020)    Antenatal screening for Down’s syndrome: Revised nuchal translucency upper truncation limit due to improved precision of measurement.                   Journal of Medical Screening        10.1177/0969141320937321 <https://doi.org/10.1177/0969141320937321>.    (In press).    Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10127016/1/0969141320937321.pdf