A New Approach to Assessing Children's Interpretation of Severity Qualifiers in a Multi-Attribute Utility Instrument-The EQ-5D-Y-5L: Development and Testing.

Introduction: The beta EQ-5D-Y-5L is a new patient-reported outcome measure (PROM) for children aged 8-15 years that is currently under development by the EuroQol Group. The EQ-5D-Y-5L is similar to the EQ-5D-Y but has five levels of severity per dimension rather than three. The increased number of levels increases the granularity of the responses but possibly has also increased the difficulty of distinguishing between levels. The EuroQoL's Version Management Committee (VMC) required a robust method to determine how well children distinguish between the five EQ-5D-Y-5L ordinal severity qualifiers (i.e. 'no problems' through to 'extreme problems'), which are a critical aspect of both health measurement and the valuation of health states.

Objective: This paper describes the development, testing, selection, and piloting of such a method.

Methods: Following a literature review and consultation with the wider VMC and a Language Support Services agency, a range of exercises were developed to assess the ordering and comprehension of the five severity qualifiers. Three exercises were pre-tested with children in Spain and New Zealand. One exercise, preferred and understood by children, was then piloted.

Results: Five children in Spain and 11 in New Zealand tested the three exercises. In both countries, all children found the three exercises easy to understand and complete. Of the 12 children who expressed a preference, nine said they preferred the card ranking. Card ranking also allowed the interviewer to observe difficult choices being made as the children physically rearranged the card order until they settled on their final order. Following rigorous assessment of translatability and cultural portability by an independent Language Support Service, card ranking was piloted in South Africa (n = 9) and in Indonesia (n = 10), where it highlighted severity qualifier order inversions that would otherwise not have been detected.

Conclusion: The card ranking exercise was found to be a preferred and acceptable means of testing the ordering of translations of severity qualifiers among children. Additional formal testing of the exercise in other countries and languages is now underway. The approach developed and tested by the VMC for cognitive debriefing of beta EQ-5D-Y-5L language/country versions may also be useful in determining the adequacy of translated qualifiers in debriefing of adult EQ-5D-5L versions and other PROMs.