A review of discrete event simulation in National Coordinating Centre for Health Technology Assessment-funded work and a case study exploring the cost-effectiveness of testing for thrombophilia in patients presenting with an initial idiopathic venous thromboembolism

Abstract

A review of modelling work funded by the National Coordinating Centre for Health Technology Assessment (NCCHTA) was undertaken to quantify the use of discrete event simulation (DES) techniques in health economics. A case study, funded by the NCCHTA, estimating the cost-effectiveness of thrombophilia testing is presented. Thrombophilia may increase the risk of venous thromboembolism (VTE) which can be fatal; however, the preventative treatment, warfarin, is associated with an increased risk of haemorrhage, which is also potentially fatal. A DES model, populated from literature reviews and incorporating VTE events, haemorrhages and death was constructed. The most cost-effective duration of warfarin treatment (‘standard treatment’ of 3 or 6 months, 10 years, 20 years or lifelong) was estimated for patients with initial idiopathic VTE, sub-divided into age, gender, VTE type and known thrombophilia type groups. The primary goal was to ascertain, for each sub-group, whether the cost of thrombophilia testing for all patients, given subsequent tailoring of warfarin duration, would be cost-effective. Thrombophilia testing was estimated to be cost-effective in most sub-groups; however these results are subject to large uncertainty. Primary research is required before a definitive conclusion can be reached.

Keywords:

• simulation
• health service
• decision analysis
• cost benefit

Acknowledgements

The following formed our clinical advisory group for the case study. Professor M Greaves, Dr T Baglin, Dr I Jennings, Dr S Kitchen and Dr M Makris. Funding for this project was provided by the National Collaborating Centre for Health Technology Assessment. The views expressed in this article do not represent those of the funder.