Evaluation Of Patient- (PRO) And Observer-Reported Outcomes (OBSRO) Measures Regarding Acceptability And Palatability Of Eltrombopag In A Pediatric Population

Abstract

The development of clinical outcome assessments for pediatric populations poses unique challenges. Consideration must be given to age-related vocabulary and conceptual comprehension. When the patient is unable to respond themselves, valid and reliable proxy measures should be used. This study evaluated the use of modified patient-reported outcome (PRO) and observer-reported outcome (ObsRO) acceptability and palatability instruments for use in pediatric studies. A review of existing acceptability and palatability instruments (of deferasirox), highlighted gaps in conceptual coverage and provided rationale for modification of the instruments, in accordance with criteria outlined in the European Medicines Agency guidance. Cognitive debriefing interviews were conducted with adolescents 12-<18years and parents of children 1-<12years with severe aplastic anemia or secondary thrombocytopenia. A “think-aloud” exercise was used, whereby respondents completed the questionnaire while speaking aloud their thoughts as they read each instruction and completed each item, to evaluate conceptual comprehension and relevance. All adolescents (n=5) and parents (n=6) demonstrated good understanding of the majority of items in the modified acceptability and palatability PRO and ObsRO instruments. Two items in the PRO instrument, related to administration and the shape of medication, were not clearly understood by adolescents (4/5 and 5/5 respondents, respectively). For consistency, suggested revisions to items in the PRO were also applied to corresponding items in the ObsRO instrument. Adolescents and adults were willing to complete the respective instruments once a week or as often as required. Conclusions drawn from the qualitative findings of this study informed key recommendations to enhance the content validity of the PRO and ObsRO instruments. Eight of 18 items in the PRO and 4 of 16 items in the ObsRO were revised. The finalized versions of the PRO and ObsRO instruments are deemed to be conceptually comprehensive based on this research, within the specific context of use.