A core outcome set (COS) is a minimum standardized set of agreed-upon outcomes for clinical trials of a specific condition. COS development can improve research by aligning stakeholder priorities for the outcomes most important in decision-making across the life-cycle of a product. It is important to include health technology assessment (HTA) representatives in COS development to ensure that outcomes useful to HTA are consistently included in clinical trials. Here we describe the role of HTA representatives in two COS projects: coreHEM, for gene therapy for hemophilia, a genetic blood clotting disease; and coreNASH, for nonalcoholic steatohepatitis (NASH), a progressive form of fatty liver disease that can lead to cirrhosis. We will describe the voting patterns of HTA representatives and consider aspects of their role in shaping the final COS.

For each multi-stakeholder COS, a modified Delphi process was utilized (three online surveys plus an in-person consensus meeting). Candidate outcome lists were compiled via a literature review complemented by participant interviews. Voters condensed and prioritized the lists by rating each outcome on a scale of 1-9 (not important-essential). Votes on each outcome were stratified by stakeholder group; HTA votes were compared with those of other stakeholders.

HTA representatives made up 12.2 percent and 13.5 percent of the voters in coreHEM and coreNASH, respectively. They tended to give the highest votes to mortality outcomes, outcomes measuring the severity of disease, and outcomes related to a patient's quality of life, general well-being and general health perspective. HTA votes helped certain outcomes meet the inclusion criteria in the final voting rounds; without HTA voters, the “mental health status” outcome in coreHEM and the “hepatic-related mortality” and “liver transplantation” outcomes in coreNASH would have been eliminated.

HTA participation in COS projects provides HTA representatives an opportunity to help shape COS in clinical research for better decision-making.