Leeds In Vitro Diagnostics Co-operative

Measurement uncertainty in Health Technology Assessments

17 April 2018

A review of Health Technology Assessments (HTAs) has shown variable and often limited evaluation of measurement uncertainty within HTAs of in vitro tests.

Systematic and or random errors in test measurements (collectively ‘measurement uncertainty’) can be caused by a variety of factors, from the time of day a test sample is taken to the specific platform used for sample analysis.

The resulting uncertainty around observed test values can have a significant impact on the ability of a test to correctly diagnose patients and effectively inform clinical decisions: the validity of conclusions from technology assessments which fail to assess the potential impact of measurement uncertainty on clinical outcomes and cost-effectiveness may therefore be questioned.

Led by Alison Smith, a research fellow in the University of Leeds’ Academic Unit of Health Economics, the study set out to systematically review international HTAs, exploring how data on in vitro test measurement uncertainty is currently assessed. The work focused, in particular, on the methods used within economic models.

The paper, published in the journal PharmacoEconomics, is the first publication from Alison’s NIHR-funded Doctoral Fellowship.

She found that, out of 107 identified HTAs, 20 (19%) attempted to assess components of measurement uncertainty: the majority of these were limited to an evaluation of a limited set of measurement uncertainty components (such as repeatability, or between-method bias) within some form of pre-model assessment (for example literature review or laboratory survey).

Only 5 studies included data on measurement uncertainty within the economic model. The paper concluded that, whilst the findings indicate that assessment of measurement uncertainty within HTAs appears to be feasible, uncertainty remains around best practice methodology for conducting such analyses.

“We know that measurement uncertainty can have a huge impact on the clinical accuracy and utility of tests, but this impact is rarely addressed within health technology assessments and typically excluded from cost-effectiveness analyses,” Alison explains. “Part of the problem is that measurement uncertainty is not well understood outside of the laboratory; our paper therefore includes a concise educational introduction to key concepts in this area to aid understanding within the HTA community which we hope will be a useful resource for researchers in the future.”

She adds: “The findings of the review are exciting for us as they clearly demonstrate a need for further research in this area, in particular to explore how such data can be captured and utilized within clinical utility and cost-effectiveness analyses. This is the focus of the next stages of our research.”

The paper, titled: ‘The Role of Measurement Uncertainty in Health Technology Assessments (HTAs) of In Vitro Tests’, can be accessed here: https://doi.org/10.1007/s40273-018-0638-1).