The Assessment of Systemic sclerosis-associated RAynaud's Phenomenon (ASRAP) questionnaire: Item Bank and Short Form Development

OBJECTIVES: To develop, refine and score a novel patient-reported outcome (PRO) instrument to assess the severity and impact of Raynaud's phenomenon (RP) in systemic sclerosis (SSc). METHODS: The Assessment of Systemic sclerosis-associated RAynaud's Phenomenon (ASRAP) questionnaire items were developed with patient insight partner support and grounded in the lived patient experience of SSc-RP. ASRAP items underwent formal qualitative assessment and linguistic testing. An international multi-center study was undertaken to field-test the preliminary ASRAP questionnaire. RESULTS: A preliminary 37-item ASRAP questionnaire was supplemented with 2 additional items following expert review to enhance content coverage before undergoing formal linguistic testing to optimize readability. Patient cognitive debriefing interviews were undertaken to enhance comprehension, ambiguity, cognitive difficulty, relevance and content coverage of both the ASRAP items and instructions. We enrolled 438 SSc patients from UK and US scleroderma centers over two consecutive winters. Factor analysis with item response theory (IRT) was undertaken to remove redundant and poorly fitting items. The retained 27-item long-form ASRAP questionnaire was calibrated and scored using the graded response model (GRM). A fixed 10-item short-form ASRAP was developed using computerized adaptive testing simulations. CONCLUSION: The ASRAP questionnaire has been developed with extensive SSc patient input, with items grounded in the lived experience of SSc-RP to ensure strong content validity, with a focus on how patients 'feel' and 'function'. An advanced psychometric approach with expert input has removed redundant and/or poorly fitting items, without eroding content validity. Long and short-form ASRAP questionnaires have been calibrated and scored to permit formal validation. This article is protected by copyright. All rights reserved