City University London Birth Data Linkage Projects

A series of projects led by City University London has linked different sources of maternity and birth data to provide new information about the relationships between gestational age, birth weight, ethnicity and mortality.

The main data sources which have been used are:

In 2004, City University London; the Office for National Statistics (ONS); the Welsh Government; and other relevant organisations in England and Wales collaborated to link these datasets for all births that occurred in England and Wales from 2005 to 2007.

Stage 1 of the project involved linkage of birth registration data with NN4B dataset and assessment of data quality and completeness of the NN4B data. This allowed socio-demographic data from birth registration data to be linked to information about gestational age and ethnicity. Furthermore, infant death records could be linked to NN4B records to produce gestation specific infant mortality rates for the first time.

Stage 2 of the project involved linkage of the dataset created in stage 1 to Maternity HES and the corresponding Welsh records for 2005 - 2007, and assessed data quality and completeness by comparison with birth registration or NN4B. This allowed comparisons of completeness where the same data items were collected in the different datasets and also linked information from Stage 1 of the project with data about maternal care during labour, such as method of delivery and complications of birth.

A number of papers have been published. Follow the links below for summaries of the publications and links to them.

Stage 1 Publications

Stage 2 Publications