Correction to: European Journal of Human Genetics (2013) 21, 943–947; doi:10.1038/ejhg.2012.288
Explanation of the error
The calculation of the maternal age risk of having a baby with Down's syndrome for the 5-year age groups was incorrect, as the arithmetic mean of 5-year maternal age risk derived from Morris' formula was used, which ignored the age distribution. This caused the estimated number of babies born with Down's syndrome to be around 5% too high. The corrected age-specific risks for each age group are as follows: 0.66 per 1000 for under 20 years of age; 0.70 per 1000 for ages 20–24; 0.84 per 1000 for ages 25–29; 1.48 per 1000 for ages 30–34; 4.72 per 1000 for ages 35–39; 15.22 per 1000 for ages 40–44; and 30.71 per 1000 for 45 years and older. The revised Table 1 is given below with the revised figures highlighted.
Table 1. Number of all births and births with Down's syndrome estimated in absence of screening and selective termination and number recorded by the NDSCR in England and Wales: 1938–2010.

The amended article appears in this issue, and the html and online PDF versions have also been corrected.
The authors would like to apologise for their error.
