Development of the Warwick Axial Spondyloarthritis faTigue and Energy questionnaire (WASTEd) – a new patient-reported outcome measure
Pearson NA., Tutton E., Martindale J., Strickland G., Thompson J., Packham JC., Creamer P., Haywood KL.
Abstract Objective To co-produce and test a potential new patient-reported outcome measure (PROM) - the Warwick Axial Spondyloarthritis faTigue and Energy questionnaire (WASTEd), providing vital qualitative confirmation of conceptual relevance, clarity, and acceptability. Methods Informed by measurement theory, we collaborated with patient partners throughout a three-stage, iterative process of PROM development. Stage 1: Informed by patient interviews, reviews exploring patients’ fatigue experiences, and existing PROMs of fatigue, an initial measurement framework of axSpA fatigue and energy and candidate items were defined. Stage 2: The relevance and acceptability of the measurement framework and candidate items were assessed qualitatively by focus group participants. Stage three: Patients participated in pretesting interviews to assess item comprehensiveness, relevance, acceptability, and comprehensibility. Results Stage one informed the development of an initial five-domain measurement framework, with 59 candidate items. In stage two, five patients and seven healthcare professionals participated in four focus groups to derive a 40-item model of fatigue and energy. Collaborative engagement with patient research partners further supported refinement of questionnaire structure and content. Pretesting with ten patients across two interview rounds in stage three produced a four-domain, 30-item long-form questionnaire. Conclusions An active collaboration with patients and healthcare professionals has supported the co-production of a potential new PROM of axSpA fatigue, underpinned by strong evidence of face and content validity. The WASTEd extends the assessment of fatigue beyond severity, highlighting the importance of symptom frequency, energy, and self-management. Future research will involve psychometric evaluation, supporting item-reduction, structural refinement, and confirmation of PROM validity.