Adopting a Societal Perspective in Health-Economic Evaluation: Analysis of Nine HTA Methodological Guidelines on How...

The perspective applied in Health Technology Assessment (HTA) has recently been presented as a central methodological debate in HTA. Beyond expected effects on patients' health and quality of life, health technologies can affect broader societal domains, such as the labor market and informal care. Ensuring comparability between treatments when estimating their impact on society relies strongly on transparency regarding the methodology used to measure and value societal costs. This study aims to describe and summarize current recommendations of HTA bodies on adopting societal perspectives in HTA.

A scoping review of HTA guidelines was conducted, and findings were validated through semi-structured interviews with academic and industry HTA experts. Guidelines from nine countries (Australia, Canada, France, Germany, The Netherlands, Spain, Sweden, United Kingdom, United States of America) were analyzed using an extraction grid covering four domains: out-of-pocket/copayment costs, informal care costs, productivity losses, and unrelated health care costs. Exploratory analyses (multiple factor analysis and clustering) assessed whether recommendations for a societal perspective as a base case were homogeneous across countries.

A societal perspective was recommended as a base case in 56% of the guidelines. Marked cross-country heterogeneity was observed for measurement methods. Only The Netherlands recommended a specific instrument for both informal care and productivity losses (iPCQ). The most frequently cited valuation approaches were the opportunity cost method (informal care) and the friction cost method (productivity losses). Three clusters of countries were identified: The Netherlands/Canada (1); US/Sweden/UK/Germany (2); and Spain/France/Australia (3). Exploratory analyses indicated limited alignment between endorsing the inclusion of societal costs and recommending the societal perspective as base case.

This preliminary work highlights the need for explicit methodological guidance on societal cost estimation within HTA. HTA bodies could draw on the Netherland's guidelines and cost database and develop a national "societal perspective doctrine"-including core cost sets, standardized measurement tools (e.g., iPCQ; diary methods), and structured involvement of patients and caregivers-to enhance comparability and decision relevance.