How reliable are the data?

The data come from the National Congenital Heart Disease Audit (NCHDA) which is managed by the National Institute of Cardiovascular Outcomes Research (NICOR). All hospitals in the UK and Ireland performing heart surgery in children have to submit their data in a standard format to NCHDA. All hospitals are independently audited each year as part of a data validation process (to check the quality of the data submitted) to ensure that the data are of high quality.

While no large dataset is perfect (it is inevitable that a few records will not be 100% accurate), this dataset is among the most detailed and complete in the world for children’s heart surgery.