Research Impact


Graphical monitoring of clinical outcomes and healthcare quality


14 December 2014


A graphical tool for monitoring clinical outcomes developed by UCL researchers has been widely adopted by UK cardiac surgery centres, and has helped a shift in culture towards more open outcome assessment in adult cardiac surgery, which has been credited with reducing mortality rates.

Work on the tool - the variable life-adjusted display, or VLAD - began in the mid-1990s, after it became clear that, in the UK, prolonged periods of poor performance by individual cardiac surgeons had been going undetected. This highlighted the need for clinical outcomes - such as mortality within 30 days after surgery - to be routinely monitored.

Researchers in UCL Mathematics developed a VLAD, a graphical tool for monitoring outcomes, in 1997. Today, regulatory bodies worldwide use it to monitor a broad range of other clinical outcomes. For example, Queensland Health uses VLAD as a major part of its Patient Safety and Quality Improvement Service to monitor 34 outcomes across 64 public hospitals, and NHS Blood and Transplant uses VLAD to monitor early outcomes of all UK transplants. 

This is a great example of constructive collaboration between academics and clinicians to give clinical teams the tools that they need for quality assurance and to further improve outcomes. - Sir Bruce Keogh, Medical Director NHS England

In the United States, VLADs have been used since 2009 by the Veterans Health Administration (VHA), the USA's largest integrated health care system, serving over 8.3 million veterans each year. VLAD charts are incorporated into the VHA's national quality improvement project to monitor mortality on acute medical and surgical units at 127 VHA centres.

Monitoring of short-term outcomes using VLADs is now conducted within many adult cardiac surgery centres in the UK and other countries. The technique enables surgical units to analyse their outcomes and also compare the outcomes of individual surgeons to ensure that any appropriate action relating to an unexpected increase in mortality can rapidly be taken and that any periods of better than predicted outcomes can be learnt from.

Although originally developed to monitor outcomes in adult cardiac surgery, the UCL team has since applied the VLAD technique in other clinical settings, including the occurrence of surgical wound infections in hospitals and monitoring outcomes after paediatric cardiac surgery. Software developed at UCL was sold under licence in 2013 to all 12 UK (NHS and private) centres performing this type of surgery. This use of VLADs has been incorporated by NHS England into the quality assurance checklist they developed for commissioners of paediatric surgery services. The relevant national audit body, NICOR (National Institute for Cardiovascular Outcomes Research), has also purchased the software and used it in a comparative analysis of outcomes in the 10 English paediatric surgery centres. Their analysis indicated that there were no safety problems in any of the centres.