RESULTS: Alternative methods should be considered for NICE cost-effectiveness assessments of treatments for pediatric rare diseases. For instance, EQ-5D is the preferred measure of health-related quality-of-life (HRQoL) in adults but no specific measures for pediatrics are recommended. There is a need for an accepted method and value set to accurately assess HRQoL of pediatrics, such as the PedsQL. Furthermore, the application of a rarity modifier in addition to the new severity modifier could allow for a greater QALY weighting for rare conditions and treatments assigned orphan designation. Lastly, a framework to assess value not captured in a QALY should be applied, allowing for the robust deliberation of additional value elements that should be factored into decision making for treatments of rare pediatric diseases, e.g. innovation, wider societal effects and patient preference.