RSS president elect David Spiegelhalter has helped to develop a new website to help people make sense of children’s heart surgery survival rates. The website, Understanding Children’s Heart Surgery Outcomes, helps to communicate that high-performing hospitals could have lower survival rates because they take on the most complex cases.
Using a method called partial risk adjustment in surgery (or PRAiS), the website shows that each hospital’s survival rate should only be compared to it a predicted range - determined by factors such as the complexity of the procedures it carries out.
'There is an understandable urge to put hospitals in a league table when comparing survival rates,’ said David, who is Winton Professor for the Public Understanding of Risk at Cambridge. 'But rather than try and directly compare hospitals with each other, we need to compare a hospital’s survival rate with what we would predict it to be, taking into account how severe their cases are. This is a tricky idea but, with the help of many families, I think we have made it clear.’
David helped develop the website with Christina Pagel, a reader in operational research at University College London, in collaboration with the charity Sense about Science and experimental psychologist Tim Rakow from King’s College London. Using the available survival data currently published by the National Congenital Heart Disease Audit (NCHDA), the researchers used PRAiS to calculate a predicted range of survival for each specific hospital, taking into account the complexity of each individual child’s medical condition and surgery.
The website explains why no hospital has exactly the same predicted range of survival - because each hospital treated different children. It also sets out why, if a hospital's survival rate is below its predicted range, it need not indicate alarm, but rather serves as a trigger for further investigation.
With more than 97% of children now surviving to at least one month after surgery in the UK and Ireland, it’s hoped that childrensheartsurgery.info will help to allay parent’s fears about each hospital’s survival rate record. Bob Ward, a grandparent of a heart patient, explains how misinterpreted data can cause enormous worry to families: ‘There have been occasions when sensational, misleading and scary headlines in the media - sometimes based on incomplete or inaccurate data - have caused enormous and unjustified concern, particularly to families whose child was about to undergo surgery,’ he says. 'This website goes a long way towards providing clear, accessible and objective information to everyone, professionals and public alike.'
David and Christina are calling for other researchers, companies and government to make health statistics more accessible to patients and families by making them easier to understand and ultimately prevent confusion and unfounded anxiety.
In an article published in the Guardian newspaper, David describes the process of developing the website 'a humbling and invaluable experience'. He continues: 'I am now utterly convinced that users have to be involved from the very start. And there are so many other areas that could benefit from this approach, which might help dislodge the obsession with simplistic league tables.'