P487 Development and validation of a new patient-reported outcome measure for Crohn’s perianal fistula: Crohn’s anal fistula quality-of-life (CAF-QoL) scale

Abstract

Abstract Background Crohn’s perianal fistulas are challenging for patients and clinicians. Many do not respond to available treatments, and despite recommendations by a recent global consensus, there are currently no specific patient-derived quality of life (QoL) tools to measure outcomes including response to treatment, in patients with Crohn’s perianal fistulas. Exploratory qualitative work has demonstrated that Crohn’s perianal fistulas reduce QoL far beyond restricting daily and sexual activities, and a patient-centred, patient-derived tool is needed. We present a patient-reported outcomes measure (PROM) for this complicated disease phenotype. Methods A 35 item draft questionnaire was generated using information from: (a) unstructured qualitative patient interviews, exploring the experience of living with Crohn’s perianal fistulas; (b) a consensus exercise analysing outcomes from a systematic review of studies assessing medical, surgical and combined (medical/surgical) treatment of Crohn’s perianal fistula; and (c) a patient and public involvement meeting. Psychometric properties were assessed including construct validity (by comparison with the Hospital Anxiety and Depression Scale, HADS and the United Kingdom version of the Inflammatory Bowel Disease Questionnaire, UK-IBDQ), and reliability and responsiveness assessed by test-retest analysis. Results Data from 211 patients contributed to the development of the CAF-QoL scale, following the collation of items including patient experience interviews, a systematic review and a consensus exercise involving 187 stakeholders (patients, gastroenterologists, surgeons, IBD specialist nurses, radiologists). Internal consistency was good with Cronbach’s α of 0.88. Analysis aided reduction of the questionnaire to 26 items that demonstrated good internal consistency, good stability (intra-class correlation 0.98) and good construct validity and responsiveness with positive correlation with the UK IBDQ and HADS. Conclusion A disease-specific PROM to assess clinical outcome (i.e. QoL) as baseline and following interventions in patients with Crohn’s anal fistula—the CAF-QoL—is ready for use. Translation and cross-cultural validation will aid wider international dissemination.