Purpose: Establishing a meaningful within-individual change (MWIC) threshold is a key aspect for interpreting scores used as endpoints for evaluating treatment benefit. A new patient-reported outcome (PRO), a sleep disturbance numerical rating scale (SD NRS), was developed in adults and adolescents with moderate-to-severe atopic dermatitis (AD). This research aims to establish a MWIC threshold of the SD NRS score in the context of a drug development program.
Methods: An explanatory sequential mixed-methods design was used to address the research objective. This mixed-methods design used phase IIb data and a stand-alone qualitative study. Quantitative anchor-based and distribution-based approaches supported by qualitative-based approaches were conducted, and results were triangulated to determine preliminary MWIC thresholds of the SD NRS score.
Results: Triangulation of results from both quantitative and qualitative approaches suggested that a 2- to 6-point decrease in the SD NRS score change constitutes a preliminary range of MWIC threshold estimates.
Conclusion: This research determined MWIC threshold estimates for the SD NRS score in both adolescents and adults with moderate-to-severe AD using an explanatory sequential mixed-methods design. This mixed-methods design provides interesting insights for establishing MWIC thresholds of a PRO score in the context of a drug development program.
Keywords: Atopic dermatitis; Meaningful within-patient change; Mixed-methods research; Multi-stage mixed methods design; Sleep disturbance; Triangulation.
© 2022. The Author(s).