Children’s heart surgery website aims to end confusion over survival rates

BMJ 2016; 353 doi: (Published 24 June 2016) Cite this as: BMJ 2016;353:i3539
  1. Matthew Limb
  1. London

Researchers have launched a website to help end public “confusion and alarm” about survival data on children’s heart surgery outcomes in the United Kingdom and Ireland. They said that the government, scientists, companies, and other bodies should do more to make health statistics understandable to patients and their families.

The website, Understanding Children’s Heart Surgery Outcomes,1 which is supported by the charity Sense about Science, explains the 30 day survival rate after children’s heart surgery. The charity’s director, Tracey Brown, said that “overinterpretation of faulty data” in 2013 had caused alarm for patients’ families and the temporary closure of Leeds General Infirmary’s paediatric heart unit.

“This website draws a line under an era of poor risk communication of hospital surgery statistics,” she said, adding that policy makers and the media could also benefit from using it.

Until now people have been able to access survival data in the National Congenital Heart Disease Audit. But researchers said that the published audit report is long, hard for people to find, and hard to understand without expert knowledge.

The new website seeks to make the data more accessible, easier to view graphically, and easier to interpret. It also explains how data have been calculated using a risk adjustment formula, what its limitations are, and why lower survival rates need not trigger alarm but merit further investigation.

Christina Pagel, a reader in operational research at University College London, developed the website with David Spiegelhalter, who is Winton professor of the public understanding of risk at Cambridge University and played a leading role in the public inquiries into children’s heart surgery at Bristol Royal Infirmary.

Pagel developed the formula known as PRAiS (partial risk adjustment in surgery), which has been used for the national heart disease audit since 2013. The formula is used to calculate a “predicted range” of survival at each hospital, taking into account the complexity of a child’s medical condition and surgery. High performing hospitals can have lower survival rates simply because they take on the most complex cases.

Spiegelhalter said that, despite an “understandable urge” to place hospitals in league tables, directly comparing survival rates between hospitals was not valid. He told The BMJ, “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.”

The project was funded by the National Institute for Health Research’s health services and delivery research programme. It was part of a £244 000 (€319 000; $363 000) grant that also covered work to modernise the risk formula.

Spiegelhalter said, “The basic principle of involving the intended audience right from the start is not generally how official communication is done.” He said that merely making data available or transparent was “not enough” if no effective tools were provided to enable proper understanding or interpretation.

Marta Salamonowicz, information and research manager for the Children’s Heart Federation, said that many patients found hospital survival statistics confusing. “This website shows much more clearly the 30 day survival rate and hopefully will ease parents’ worries about where their child should be treated,” she said.



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