Presentation (CTI)

OBJECTIVES: Economic evaluation of obesity interventions is complex, driven by long-term benefits and interactions with multiple comorbidities, resulting in heterogeneous modelling approaches. In May 2026, NICE published its first disease-specific reference case extension (RCE) for the management of overweight and obesity in adults (PMG50), setting standardised methods for economic evaluation. This study describes its development and role in improving consistency, transparency, and decision making.
METHODS: The RCE was developed through an iterative multi-stakeholder process. A targeted review of published economic models was undertaken to identify key methodological challenges and variations. Stakeholder workshops with clinicians, patient representatives, health economists, industry and NHS commissioners captured best practice and areas of consensus. The RCE was drafted through collaboration across NICE’s guidance programmes (Guidelines, HealthTech and Medicines Evaluation) and subsequently refined following a public consultation with a broad range of stakeholders.
RESULTS: The RCE specifies core modelling elements including population stratification, comparators, model structure, and data. A key requirement is stratification of results by type 2 diabetes (T2DM) status, atherosclerotic cardiovascular disease status and weight category (overweight or obesity) to reflect heterogeneity of cost effectiveness. State transition modelling approaches are preferred. It prioritises directly measured outcomes (such as stroke, myocardial infarction and onset of T2DM) from trials alongside real-world evidence for baseline risks. Health-related quality of life should be valued using EQ‑5D, with utilities modelled as a function of body mass index, comorbidities, age, and sex. Consideration of health inequalities, including distributional cost-effectiveness analysis, is described. The RCE distinguishes between “required” and “recommended” statements and applies across NICE programmes.
CONCLUSIONS: The obesity RCE provides a structured yet flexible framework for economic evaluation, improving consistency and transparency. It supports more robust evaluations and more efficient updates to guidance and will serve as a guide for future disease-specific RCEs to strengthen NHS decision making and resource allocation.