Validation of a novel patient reported tool to assess the impact of treatment in erythropoietic protoporphyria: the EPP-QoL.
G BiolcatiS HannekenE I MinderN J NeumannJ H P WilsonP J WolgenD J WrightAndrew J LloydPublished in: Journal of patient-reported outcomes (2021)
Based on the analysis it was recommended to drop the EPP Wellbeing domain (and associated items). EPP Symptoms, despite limitations in the development of items, showed evidence of validity. This work is consistent with the recommendations of a task force that provided recommendations regarding the development, modification and use of PROs in rare diseases.