Thin line between research and audit

Abstract

The paper by R J M Snijders and colleagues published in today's Lancet and discussed in the preceding commentary shows the extent to which measurement of nuchal translucency can help in the antenatal detection of Down's syndrome. So is there reason to question whether The Lancet should have published the paper? Antenatal screening for Down's syndrome: where are we and where next?The ability to identify Down's syndrome at a time in gestation when choices about termination can be made dates from the 1970s. Initially, the only available screening test was a question—the woman was asked her age. The likelihood of Down's syndrome increases as the pregnant woman's age advances.1 In the USA, 35 years of age was adopted as the screening cut-off, and pregnant women above that age were routinely offered diagnostic testing. In the UK the age cut-off varied between 35 and 37 years of age in different regions, depending on the availability of diagnostic resources. Full-Text PDF UK multicentre project on assessment of risk of trisomy 21 by maternal age and fetal nuchal-translucency thickness at 10–14 weeks of gestationSelection of the high-risk group for invasive testing by this method allows the detection of about 80% of affected pregnancies. However, even this method of risk assessment requires about 30 invasive tests for identification of one affected fetus. Full-Text PDF