My primary research interests are in:

  • Stochastic OR, including queueing theory, simulation methods, optimisation, and game theory

  • Mathematical modelling of healthcare systems

  • Mathematical modelling for the prevention, early detection and treatment of diseases

  • Machine learning and data mining techniques

Healthcare systems are typically characterised by complexity, variability, uncertainty and use of scarce resources. To model such systems requires the development of suitable mathematical and simulation models that are able to account for the stochastic conditions, complex and large-scale patient pathways and disease processes, and at both operational and strategic levels. Various novel approaches have been developed by myself and colleagues at Cardiff (and with collaborators worldwide), including those in queueing and game theoretic models (for example time-dependent and priority queues, and routing games), hybrid simulation methodologies (DES, Agent-based, SD, Monte Carlo methods), location theory and optimisation, social network models for disease propagation, and health behavioural models.

Funding has come from many different sources to support my research and translational findings, including EPSRC, The Royal Society, The Leverhulme Trust, Nuffield Foundation, NIHR, ESRC, Health Foundation, the Department of Health, Welsh Government, and various NHS partners.

I was delighted to establish a mathematical modelling unit in collaboration with the Aneurin Bevan University Health Board and Cardiff and Vale University Health Board. A team of post-doctoral research associates/fellows, a lecturer in OR, and several PhD students have been funded by ABUHB and CVUHB, and they work between the University and Health Board (as researchers -in-residence). In addition other NHS partners regularly fund both PhDs and post-docs with our group.

In 2015 the team won a University Innovation award for our research and impact, and a prestigious Times Higher Education award for ‘Outstanding Contribution to Innovation and Technology' and in 2021 the Lyn Thomas Impact Medal from the Operational Research Society. See also Saving Lives with Maths.

My research, and that with many collaborators, has led to sustained impact and significant benefits to the NHS and patient care, resulting in increased efficiency and effectiveness of healthcare systems, and improved outcomes. Projects have included reducing waiting times, reducing elective patient cancellations, ambulance modelling (forecasting demand, location analysis, crew rostering), finding the most effective and equitable locations on for healthcare facilities, advising on the cost-effectiveness of strategies for preventing and screening for disease such as informing policy on cancer, HIV/AIDS and Chlamydia screening.

"My Innovative Life" by Cardiff University.

Please take a look at:

  • My current list of publications.

  • Research related materials including a good overview here of queueing systems in healthcare and Maths Saves Lives! video.

  • BeDMaSH - I'm one of the investigators of the GW4 network on Behavioural and Decision Making Sciences in Healthcare.