Healthcare Modelling

My research interests may be divided into two broad themes of mathematical and simulation modelling for healthcare: 

• Planning and management of healthcare resources.
• Prevention, early detection and treatment of disease.

Projects typically comprise of a mixture of theoretical and practical investigations, and many projects have been funded by external organisations, including various funding councils, Department of Health, NHS Information Centre, NHS Trusts and Primary Care Trusts. 

Particular research contributions and impacts are reported under each of these sub-headings below.

Planning and management of healthcare resources

Particular contributions include stochastic models for integrated healthcare resource systems (hospital bed capacities, theatre scheduling and workforce planning), novel research on stochastic facility location problems, multi-level simulation, conditional phase-type modelling and combined data mining and simulation methodologies.

My research has had direct input into formulating health policy, such as helping a number of hospitals plan for and schedule key resources.  For example, 10 UK hospitals are now using my PROMPT software to plan their bed and workforce needs (Harper, 2002; Harper and Shahani 2002; Harper et al. 2010). Funding for my research in to whole-level hospital planning tools has come from the NHS Workforce Development Confederation (2003-04, £24k) and an ESPRC CASE Award (2002-2005) in addition to funding directly from several NHS Trusts.  My research also contributed to an official Department of Health’s review of adult critical care services (Department of Health, 2000) and subsequent work on modelling critical care services with a number of NHS Trusts has examined resource capacities and short-term bed planning and elective scheduling (Costa et al., 2003; Ball et al., 2004).  More recently, as part of the RIGHT (Research into Global Healthcare Tools), a 2-year programme with Brunel, Cambridge, Cardiff, Southampton  and Ulster funded by the EPSRC (2007-2009, £1.1m), research was undertaken to understand barriers to adoption of OR models in the health service.  Resulting outputs included a web-based method selection tool and published handbook for NHS users (Brailsford et al., 2009; Jun et al., 2010).  Currently I am working with the Met Office and several hospitals on forecasting emergency demand and hospital resources linked to meteorological events.  This work is funded by the EPSRC (2010-2012, £344k).

Other notable areas of impact are:

• Research on emergency medical services/ambulance locations and forecasting of demand with the Welsh Ambulance services NHS Trust (Williams et al., 2010)
• Novel research on facility-location modelling (Harper et al., 2005; Harper ; Shahani et al.,2005; Smith et al., 2009).  Applications of the research have included working with the Leeds Teaching Hospitals NHS Trust (community care centres), Kings College London (dental services) and Department of Health (cardiac services, and cleft lip and palette);
• Development of data mining and decision tree tools for assisting the NHS Information Centre with the redesign of Healthcare Resource Groups (HRGs) (Harper and Leite, 2008).  Funding from the NHS Information Centre (2004-07, £92k).  As part of this project, Harper was an invited member of the UK Department of Health chronic diseases expert reference panel.
• Optimising the skill-mix of the dental workforce team and forecasting dental care needs for England.  Research for the British Dental Society (Kleinman et al., 2009)
• Hybrid multi-level simulation (combined DES and SD) funded by the EPSRC (2005, £6,330).
• Modelling the future demand for residential care in an ageing population (funding from a joint EPSRC/ESRC PhD studentship, 2006-2009);
•  ‘TORCH: Teaching OR to Commissioners of Healthcare’ for the NHS Institute (£59k, 2009) – constructing an OR education programme for NHS staff.

Prevention, early detection and treatment of disease

Particular contributions include semi-Markov and simulation models for modelling the cost-effectiveness of various strategies for preventing and screening for disease including breast cancer, colorectal cancer, HIV/AIDS and diabetic retinopathy, targeted screening programmes for Chlamydia, and novel research on healthcare behavioural modelling.

My research has had direct input into informing national health policy through work on modelling Chlamydia (Evenden et al., 2005 and 2006).  This research, as part of the Department of Health’s evaluation into the cost-effectiveness of introducing a national Chlamydia screening programme for England,  combined GIS mapping, statistical analysis and epidemiological modelling for a unique holistic view of tackling the rapid growth in the population with this sexually transmitted infection.  Our recommendation on targeted strategies for interventions, and the conditions under which screening is cost-effective, were adopted by the partner GU clinic at Portsmouth hospital and helped to inform the national programme which was then rolled out to 10 cities in England and is now a national policy.  Research published in the Journal of the OR Society was awarded the 2006 OR Society Goodeve medal (Evenden et al., 2006).

Sophisticated and complex simulation models for the evaluation of medical interventions may not necessarily truly reflect what happens in the real world, because such models do not account for human behaviour. I have contributed to novel research by combining both physiological and psychological elements in to one simulation, using breast cancer to illustrate the concept (Brailsford et al., 2006 and 2010). When experimenting with different psychological models, we conclude that the method by which a simulation model chooses to model attendance is important to the modelled outcome.  The model results indicate that increasing attendance through education or publicity campaigns can be equally as effective as decreasing the intervals between screens

Other notable areas of impact are:

• Research on small world models for the dynamics of HIV infection (Vieira et al., 2010).  This research recognises that the structure of social networks play an important role in the dynamics of disease propagation, and describes the development of a model, based on the small world principles, to model the dynamics of HIV infection.  We use the model with HIV incidence data from Brazil to demonstrate the importance of topology and initial distribution of infection, and capture the direct and non-linear relationship between the probability of a casual partnership and spread of HIV.  In summary this research progresses both small world theory for propagation of disease whist applying OR methods to social networks in a novel way.
• Semi-Markov modelling for modelling screening and treatment strategies for Colorectal Cancer, working in collaboration with consultants at the Royal Haslar Hospital (Harper and Jones, 2005).
• Research on the economic impact of occupational injuries and resource allocation for prevention programs, funded by AUVA, the largest single insurance company in Austria, and joint work with the University of Vienna (Rauner et al., 2005).

Other indicators of impact

• Winner of OR Society’s Goodeve Medal (2006) for the best paper published in the Journal of the Operational Research Society.
• Director of hmc2, a pan-Wales centre bringing together research expertise in mathematical and computational modelling applied to health (www.hmc2.org)
• Invited steering committee member of the EPSRC-funded network MASHnet (Network for Modelling and Simulation in Health).
• Active member of the UK Operational Research Society; Sat on General Council and Education and Research Committee (ERC) for 6 years (2003-2009); Chair of the ‘OR in Schools’ national taskforce (2006-current).
• I sit on the Joint Mathematical Council, as OR Society Representative, discussing UK mathematics educational matters.
• Chair of the UK Young OR Conference (Bath, 2003); Programme Chair of ORAHS, (Southampton, 2005); Chair of OR50, 50th annual conference of the UK OR Society (York, 2008); Chair of ORAHS, Euro working group on OR Applied to Healthcare (Cardiff, 2011).
• Invited plenary talks, including within the last 12 months:  OR51 (Warwick, September 2009), IEEE Workshop on Health Care Management (WHCM) (Venice, February 2010), Gregynog Statistical Conference (Gregynog, April 2010) and the Conference of Applied Statistics in Ireland (CASI) (Portrush, May 2010).
• On the editorial board of Mathematical Modelling and Applied Computing. 
• Invited editor of five special issues in Journal of the Operational Research Society, IMA Journal of Management Mathematics, International Journal of Healthcare Information Systems and Informatics, and the European Journal of Operational Research.

Research grants and contracts (2006 onwards)