Uncertainties in evaluating the health-related quality of life and disease burden of people with rare diseases and their caregivers in NICE HST submissions.

Background and aims: The NICE Highly Specialised Technology (HST) programme evaluates interventions for very rare conditions within the UK. This review aimed to analyse previous NICE HST appraisals and determine commonly used methods to overcome uncertainties relating to health-related quality of life (HRQoL) and disease burden for people with rare diseases and their caregivers. The review also aimed to identify areas where further methodological development is required.

Approach and results: A targeted review of all previous NICE HST appraisals published by the 28th February 2022, in which at least one committee meeting had taken place, was conducted. A total of 24 appraisals were included (17 fully completed and seven ongoing). Data were extracted by one reviewer. The evidence review group (ERG) and committee comments were compared against the NICE reference case and synthesised to identify the following methodological uncertainties that occurred most commonly: using alternatives to the EuroQol-5 Dimension (EQ-5D), sourcing HRQoL data from single-arm studies, measuring caregiver disutilities and estimating disease burden.

Conclusions: This review has highlighted the need for new methodology to reflect the impact of the diseases on people with rare diseases and their families. The review identified the following methodological requirements: alternative approaches that should be used when EQ-5D is not appropriate, methods to evaluate paediatric HRQoL and methods to quantify disease burden. This review also highlights the need to establish clear recommendations on the estimation of utilities across different rare diseases.