Skip to main content

Follow up and evaluation of the Victorian first-trimester combined screening programme for Down syndrome and trisomy 18

Buy Article:

$51.00 plus tax (Refund Policy)

Abstract:

Objective

The objective of this study was to follow up and evaluate the statewide first-trimester combined screening programme for Down syndrome and trisomy 18 at Genetic Health Services Victoria, Australia. Design

Retrospective population cohort. Setting

Maternal Serum Screening Laboratory records. Sample

All women screened between February 2000 and June 2002 (16 153 pregnancies). Methods

Screening results were matched to Victorian perinatal and birth defect data via record linkage, with an ascertainment of 96.8% of pregnancy outcomes. Manual follow up with health professionals increased ascertainment to more than 99%. Main outcome measures

Fetal Down syndrome or trisomy 18, and combined screen results, to calculate test characteristics. Results

Using a risk threshold of 1 in 300 at time of ultrasound, the sensitivities for standard first-trimester combined screening and augmented 13-week combined screening for Down syndrome were 87.3 and 90.5% and the false-positive rates (FPR) were 4.1 and 3.9%, respectively. The sensitivity for trisomy 18 was 66.7% (10/15, 95% CI 42.8–90.5%) with a 0.4% FPR and 15.2% positive predictive value (1 in 250 risk threshold). Conclusions

The combined use of record linkage and manual follow-up techniques was effective in ascertaining more than 99% of pregnancy outcomes for calculations of accurate test characteristics of the combined screen. The sensitivity for Down syndrome at Genetic Health is comparable to similar populations. However, the sensitivity for trisomy 18 is lower than that elsewhere, which may reflect the overall low birth prevalence of trisomy 18 and associated small numbers in this particular cohort.

Keywords: Down syndrome; first trimester combined screening; prenatal screening; test characteristics; trisomy 18

Document Type: Research Article

DOI: http://dx.doi.org/10.1111/j.1471-0528.2007.01349.x

Affiliations: 1: Public Health Genetics, Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia 2: Genetic Health Services Victoria, Royal Children’s Hospital, Parkville, Victoria, Australia 3: Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia

Publication date: July 1, 2007

bsc/bjo/2007/00000114/00000007/art00007
dcterms_title,dcterms_description,pub_keyword
6
5
20
40
5

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more