Capturing quality of life in pouch anal and vaginal fistula: development of PAVF-QoL-14, a patient-reported outcome measure.

Abstract

Perianal pouch fistula can significantly affect quality of life, yet no disease-specific patient reported outcome measure (PROM) exists. We have developed and validated a 14-item PROM-the Pouch Anal and Vaginal Fistula Quality of Life scale (PAVF-QoL-14). COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidance for PROM development was used to develop and validate PAVF-QoL-14. A systematic literature review and semi-structured patient interviews (n = 14) identified key domains. Cognitive interviews and item-level content validity index with experts refined the draft questionnaire. Psychometric evaluation included principal component analysis (PCA), internal consistency testing, and construct validity assessment against Hospital Anxiety and Depression Scale (HADS) and Short-Form 12 (SF-12). Test-retest analysis was performed on 76 patients. An initial 34-item draft scale was generated and refined through cognitive interviews (n = 10) and psychometric testing (n = 76). Flesch readability score was 63%. Kaiser-Meyer-Olkin test confirmed sampling adequacy (KMO = 0.905), and correlations between items were found significant using Bartlett's test of sphericity (p < 0.001). Four domains (symptoms, discharge, faecal incontinence, and future concerns) were extracted, explaining 63.7% of the total variance. Following stepwise regression, a 14-item short-form was developed, demonstrating excellent internal consistency (Cronbach's α = 0.920). Responsiveness was good (effect size 0.77), and test-retest reliability demonstrated excellent stability (ICC = 0.924). Construct validity was supported by moderate-to-strong correlations with HADS (r = 0.589, p < 0.001) and SF-12 (r = 0.525, p < 0.001). The final questionnaire generates scores ranging from 14 to 70, with higher scores indicating greater fistula-related impairment in quality of life. PAVF-QoL-14 provides a concise, validated, and disease-specific measure of quality of life for pouch-related fistula and shows strong potential for use in clinical practice and clinical trials. People who have an ileoanal pouch can sometimes develop a pouch anal or vaginal fistula, which is an abnormal connection that may cause ongoing discharge, pain, infections, and emotional distress. These symptoms can have a major impact on daily activities, relationships, work, and overall wellbeing. Despite this, there has been no questionnaire specifically designed to measure how pouch-related fistulas affect quality of life from the patient’s perspective.In this study, we developed and tested a new questionnaire called the Pouch Anal and Vaginal Fistula Quality of Life questionnaire (PAVF-QoL-14). Patients with lived experience of pouch fistula were involved throughout the process, starting with interviews to identify the symptoms and concerns that mattered most to them. The questionnaire was then refined through patient feedback and expert review to ensure that the questions were clear, relevant, and easy to understand. We tested the questionnaire in a group of patients and showed that it is reliable, meaning people gave similar answers when their condition had not changed, and responsive, meaning scores changed appropriately when symptoms improved or worsened. The final questionnaire contains 14 questions covering areas such as symptoms, discharge, bowel control, tiredness, emotional wellbeing, intimacy, and worries about the future. PAVF-QoL-14 is a short, patient-centred tool that can be used in routine clinical care and in research studies to better understand the impact of pouch fistula and to assess whether treatments improve quality of life.