HEE: Developing a reference protocol for expert elicitation in health care decision making

In many countries, decisions concerning the adoption of new health technologies (e.g. drugs, diagnostics) are informed by evidence relating to the cost effectiveness of competing interventions. The range of costs considered in the assessment of cost effectiveness will depend on the perspective of the analysis, with a health service perspective implying a more narrow range of costs than a societal perspective. In terms of relevant outcomes (health benefits), many national and regional decision makers require that outcomes reflect both mortality and morbidity effects, with the latter typically measured using the EuroQol 5-dimension (EQ-5D) instrument, a generic preference-based measure of health-related quality of life (HR-QOL or utility), which can be used to generate quality-adjusted life-years (QALYs). 

This project considers the current approaches to predict long-term costs and utilities, highlights some of the challenges with the existing methods, and provides recommendations for future applications. It finds that, typically, economic evaluation models employ a simplistic approach to temporal extrapolation of costs and utilities. For instance, their parameters (e.g. mean) are typically assumed to be homogeneous with respect to both time and patients’ characteristics. Furthermore, costs and utilities have often been modelled to follow the dynamics of the associated time-to-event outcomes. However, cost and utility estimates may be more nuanced, and it is important to ensure extrapolation is carried out appropriately for these parameters.

Read more about our research by reading our paper on Informing reimbursement decisions using cost-effectiveness modelling: a guide to the process of generating elicited priors to capture model uncertainties.