HEMA publishes draft guidance on evaluating uncertainty in health economic evaluations

HEMA's draft report sets out proposed approaches for analyzing, presenting and communicating uncertainty in health economic evaluations, with recommendations intended to support more consistent health technology assessment (HTA) decision-making.

The Baseline

• HEMA has published a draft report examining approaches to evaluating, presenting, and communicating uncertainty in health economic evaluations.
• The report outlines methods to characterize uncertainty, assess its implications for decision-making, and improve how uncertainty is communicated to stakeholders.
• The publication marks HEMA's second major methodological report, following its earlier work on broadening benefits considered in economic evaluation, which generated significant debate across the HTA community.

The Health Economics Methods Advisory (HEMA) has published a draft report examining how HTA organizations should evaluate, present, and communicate uncertainty in health economic evaluations. The report is now open for public consultation until November 2, 2026, ahead of publication of the final guidance in early 2027.

The 96-page report reviews approaches to characterizing uncertainty in economic evaluation and its potential consequences for population health. It also examines frameworks for analyzing multiple sources of decision uncertainty, proposes approaches for responding to uncertainty during HTA, and considers how uncertainty can be communicated more effectively to decision-makers and other stakeholders.

The topic reflects a growing challenge for HTA organizations as medicines are increasingly assessed using evidence packages that extend beyond traditional randomized controlled trials. Rather than focusing solely on quantifying statistical uncertainty, the report argues that uncertainty analyses should help decision-makers understand the consequences of making the wrong reimbursement decision. It recommends that economic evaluations assess not only the likelihood that a different decision might be preferable, but also whether further evidence could meaningfully reduce uncertainty and improve future decisions.

The report also places greater emphasis on communicating uncertainty beyond HTA committees. It recommends that patient-facing summaries explain what uncertainty means in practice, distinguish uncertainty about clinical benefit from uncertainty about value for money, identify where evidence is limited and explain how future evidence generation or reassessment could affect access decisions. The recommendations were informed by workshops involving patient representatives from Canada, the UK and the US.

Speaking recently in an interview with The Evidence Base, Mark Sculpher (University of York and Chair of the HEMA Working Group) said uncertainty is becoming an increasingly important issue for HTA organizations as more medicines reach regulators with evidence that differs from the traditional randomized controlled trial model. He said methodological research has often focused on increasingly sophisticated techniques for quantifying uncertainty while paying less attention to how decision-makers use that information in practice. The Working Group's aim, he said, is to better link uncertainty analyses with the decisions HTA organizations ultimately need to make.

HEMA was established by the leaders of three major HTA organizations, the National Institute for Health and Care Excellence (NICE), the Institute for Clinical and Economic Review (ICER) and Canada's Drug Agency (CDA-AMC), to independently examine emerging methods and processes relevant to HTA. Its recommendations are advisory, with HTA organizations free to determine whether and how they implement the guidance.

The report represents HEMA's second major methodological publication and continues the group's program of guidance on some of the most debated issues in health economic evaluation. Its inaugural report, Defining Appropriate Benefits for Economic Evaluation of Health Care Technologies, considered whether the types of benefits included in economic evaluations should evolve and proposed a framework to help HTA organizations assess potential changes. While widely recognized as an important contribution to methodological discussions, the report also attracted considerable scrutiny from researchers, payers and industry stakeholders over its recommendations for broader value assessment, prompting debate about how HTA frameworks should evolve.