Document Type

Journal Article


BMJ Publishing Group


School of Medical and Health Sciences




Bradford University studentship, in conjunction with the White Rose Consortium, and the National Institute for Health Research, Collaboration for Leadership in Applied Health Research and Care Yorkshire and Humberprogramme ‘Healthy Children Healthy Families Theme’ (IS-CLA-0113–10020)


Bishop, C., Small, N., Mason, D., Corry, P., Wright, J., Parslow, R. C., ... & Sheridan, E. (2017). Improving case ascertainment of congenital anomalies: Findings from a prospective birth cohort with detailed primary care record linkage. BMJ Paediatrics Open, 1(1), 1-11.



Congenital anomalies (CAs) are a common cause of infant death and disability. We linked children from a large birth cohort to a routine primary care database to detect CA diagnoses from birth to age 5 years. There could be evidence of underreporting by CA registries as they estimate that only 2% of CA registrations occur after age 1 year.


CA cases were identified by linking children from a prospective birth cohort to primary care records. CAs were classified according to the European Surveillance of CA guidelines. We calculated rates of CAs by using a bodily system group for children aged 0 toyears, together with risk ratios (RRs) with 95% CIs for maternal risk factors.


Routinely collected primary care data increased the ascertainment of children with CAs from 432.9 per 10 000 live births under 1 year to 620.6 per 10 000 live births under 5 years. Consanguinity was a risk factor for Pakistani mothers (multivariable RR 1.87, 95% CI 1.46 to 2.83), and maternal age > 34 years was a risk factor for mothers of other ethnicities (multivariable RR 2.19, 95% CI 1.36 to 3.54). Education was associated with a lower risk (multivariable RR 0.78, 95% CI 0.62 to 0.98).


98% of UK CA registrations relate to diagnoses made in the first year of life. Our data suggest that this leads to incomplete case ascertainment with a further 30% identified after age 1 year in our study. Risk factors for CAs identified up to age 1 year persist up to 5 years. National registries should consider using routine data linkage to provide more complete case ascertainment after infancy.



Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License