Exploring the impact of test measurement uncertainty on the cost-effectiveness of testing strategies: a case study of faecal calprotectin for Inflammatory Bowel Disease (IBD)

Alison Smith, AUHE

All clinical test measurements are subject to uncertainty. A multitude of factors along the testing pathway (relating to how the test sample is collected, stored and analysed) can affect the performance of test methods, resulting in systematic and random deviations in observed values. If, as a result, test values are incorrectly observed as lying above or below key test decision thresholds then patient management may be adversely affected. Whilst measurement uncertainty is routinely documented within the clinical laboratory, the potential impact of this uncertainty on downstream clinical, operational and economic outcomes can be difficult to quantify and, as a result, rarely attempted.

In this talk, I will first discuss findings from a recent methodology review I conducted which aimed to identify “indirect” methods (e.g. decision modelling) for estimating the impact of test measurement uncertainty on outcomes. I will then present interim findings from an application of these methods to a clinical case study exploring the use of faecal calprotectin for the diagnosis of Inflammatory Bowel Disease (IBD) in primary care. Key considerations for future development and application of these methods will be discussed.

Presenter Bio

Alison Smith is a health economist and NIHR Doctoral Research Fellow based at the University of Leeds and is currently in the third year of her fellowship. Alison’s PhD is entitled: “Developing a framework for the incorporation and utilisation of data on test measurement uncertainty with economic evaluations of in-vitro medical tests“.