ISSUE: HTAs draw on evidence that is often incomplete and immature. HTA organizations do their best to describe uncertainty’s impact on projected benefits, costs, and cost-effectiveness, but they sometimes come up short because they do not consider all plausible alternative assumptions. HTAs can miss plausible assumptions because they typically convene one group of experts and may settle on a single best option. If there are plausible alternatives, would they produce substantially different estimates? A recent study examined these questions by comparing the results of a completed HTA (Institute For Clinical and Economic Review, PARP inhibitors in ovarian cancer) with a repeat assessment performed by two independent sets of clinical and health economic experts (https://cevr.tuftsmedicalcenter.org/news/2021/unknown-unknowns). The three sets of assessments substantially differed with corresponding differences in cost effectiveness.

OVERVIEW: Moderator will frame the issue of the precision associated with assessments and its importance in determining an intervention’s cost effectiveness and associated patient access. Josh Cohen, as the principal investigator on the above study, will share what the study entailed and its findings. Nick Crabb will provide a perspective on how those results relate to NICE. Steve Pearson will provide a US perspective on both methods improvement and policy decision-making. Abigail Colson will discuss how elicitation might be improved. Moderator will engage the audience on the impact for HTAs.