Development of a new patient-reported outcome measure for complex cryptoglandular fistulas (20-Item complex cryptoglandular fistula questionnaire™): a qualitative study.

Background: There are limited tools to measure the burden of disease and effectiveness of medical/surgical interventions in patients with cryptoglandular fistulas. The aim of this study was to explore concepts that are relevant and important to patients with complex cryptoglandular fistulas (CCF) and to develop a patient-centred, disease-specific, patient-reported outcome measure (PROM) to assess symptom burden and impacts of CCF.

Methods: A targeted literature review was conducted, followed by one-to-one telephone interviews with five colorectal surgeons (USA, n = 3; UK, n = 1; Spain, n = 1) and 20 US adult patients with CCF to inform the development of a conceptual model and a CCF-specific PROM. The targeted literature review informed the development of the preliminary conceptual model and identified a PROM in the literature that was used as a reference to generate the draft CCF-specific PROM. The colorectal surgeon interviews provided insights on the experience of patients with CCF to refine the conceptual model, formulate probing questions for use in patient interviews, and to develop the draft CCF-specific PROM. Patients' descriptions of their experiences with symptoms and the impacts on their lives and evaluation of the draft CCF-specific PROM in concept elicitation and cognitive interviews were used to develop the final conceptual model and final CCF-specific PROM.

Results: Ten symptoms (odour, pain during bowel movement, abscess, post-operative pain, discharge/drainage/leakage, anal/perianal pain, inflammation/swelling, skin irritation, bleeding and itchiness) and 11 impacts (discomfort, inability to exercise, embarrassment, difficulty sitting, worry about disease, adapted life to maintain hygiene, negatively impacted social life/isolation, inability to perform daily activities, reduced interest in sex, negatively impacted intimate relationships and negatively impacted mood) were reported as most salient by patients. The patient experience, clinician perspective, and literature review provided input to item generation. Evaluation of relevance and patient understanding through cognitive interviews with patients provided evidence for the content validity of the new patient-reported outcome measure: the 20-item Complex Cryptoglandular Fistula Questionnaire^™ (CCFQ-20^™).

Conclusion: The CCFQ-20^™ is a new clinician-guided, patient-validated, disease-specific patient-reported outcome measure that measures disease impact and quality of life in patients with CCF.