Trends and Tensions in NICE Severity Modifiers: Analyzing the Acceptance and Critique of Manufacturer Severity Modifier Proposals in Recent Appraisals
Author(s)
Jessica Mounty, BVSc, Molly Haycock, PGDip, Rebecca Beale, MA.
Costello Medical, London, United Kingdom.
Costello Medical, London, United Kingdom.
OBJECTIVES: The National Institute for Health and Care (NICE) severity modifier was introduced in February 2022 to adjust the value placed on health gains by assessing absolute and proportional quality-adjusted life year (QALY) shortfall. Committee acceptance of the manufacturer’s severity modifier and associated methodology has a significant impact on cost-effectiveness. This research characterises recent manufacturer methods for calculating severity modifiers, and their alignment with External Assessment Group (EAG) and committee preferences.
METHODS: NICE appraisals considering severity modifiers with final guidance published between 01 November 2024 and 31 May 2025 were identified. Details of the severity modifier calculations adopted by the manufacturer, modifier values proposed, EAG critique and committee acceptance, were extracted.
RESULTS: Database searches yielded 57 appraisals, of which 13 considered a severity modifier in one or more populations. Of nine appraisals proposing a x1.2 modifier in the full population or a subgroup, all were awarded. Of seven appraisals proposing a x1.7 modifier in the full population or a subgroup, only four were awarded, with the remaining awarded a x1.2 modifier. EAGs expressed concerns over uncertainty in the proposed modifier in six appraisals, and explored the impact of uncertainty through alternative methods or data inputs. In one such appraisal, the manufacturer conducted 35 scenarios alternating comparator survival extrapolations alongside scoring algorithms, health state profiles and models within a modifier calculation tool, with the modifier ultimately gaining committee acceptance. Reasons for critique and non-acceptance were application of modifiers to caregiver QALYs, use of inappropriate discount rates in the cost-effectiveness model and citing previous acceptance of end-of-life criteria.
CONCLUSIONS: For the majority of appraisals, proposed severity weightings were awarded, though x1.7 modifier proposals were less frequently accepted. Methodology deviations from Technical Support Document 23 are unlikely to be accepted, but exploration of scenarios may reassure the committee of proposed modifiers in the presence of EAG critique.
METHODS: NICE appraisals considering severity modifiers with final guidance published between 01 November 2024 and 31 May 2025 were identified. Details of the severity modifier calculations adopted by the manufacturer, modifier values proposed, EAG critique and committee acceptance, were extracted.
RESULTS: Database searches yielded 57 appraisals, of which 13 considered a severity modifier in one or more populations. Of nine appraisals proposing a x1.2 modifier in the full population or a subgroup, all were awarded. Of seven appraisals proposing a x1.7 modifier in the full population or a subgroup, only four were awarded, with the remaining awarded a x1.2 modifier. EAGs expressed concerns over uncertainty in the proposed modifier in six appraisals, and explored the impact of uncertainty through alternative methods or data inputs. In one such appraisal, the manufacturer conducted 35 scenarios alternating comparator survival extrapolations alongside scoring algorithms, health state profiles and models within a modifier calculation tool, with the modifier ultimately gaining committee acceptance. Reasons for critique and non-acceptance were application of modifiers to caregiver QALYs, use of inappropriate discount rates in the cost-effectiveness model and citing previous acceptance of end-of-life criteria.
CONCLUSIONS: For the majority of appraisals, proposed severity weightings were awarded, though x1.7 modifier proposals were less frequently accepted. Methodology deviations from Technical Support Document 23 are unlikely to be accepted, but exploration of scenarios may reassure the committee of proposed modifiers in the presence of EAG critique.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
HTA342
Topic
Economic Evaluation, Health Technology Assessment
Topic Subcategory
Decision & Deliberative Processes
Disease
No Additional Disease & Conditions/Specialized Treatment Areas