Bowel Irrigation Questionnaire Development of a Patient-Reported Experience Measure to assess the user experience of Transanal Irrigation

Aims To develop the Bowel Irrigation Questionnaire (BIQ), a patient-reported experience measure (PREM) designed to assess the user experience of transanal irrigation (TAI). Methods Statements were generated through literature review and qualitative interviews with healthcare professionals (HCPs) and product users. Statements were rated on a 6-point content validity index scale through an international three-round online Delphi survey by 20 expert panel members. Consensus attainment was defined based on percentage agreement, statements which did not meet consensus were discussed at a final international online consensus meeting. The content validity of the PREM was evaluated through cognitive interviews and the Questionnaire on Questionnaires (QQ-10). Reliability was assessed using a test-retest design, where users completed the BIQ on two occasions one week apart. Results 215 statements were generated from 9 multi-disciplinary qualitative interviews and literature review. Statements were refined to reduce repetition and ensure clarity. 73 statements grouped into 11 domains were reviewed through the Delphi survey. Following the Delphi survey and clinical consensus meeting, the preliminary BIQ consisted of 15 items. Six cognitive interviews were conducted, resulting in a finalised BIQ of 16 items. 32 product users completed both the QQ-10 and test-retest study, the results of which demonstrated good content validity and temporal stability respectively. Conclusions The Bowel Irrigation Questionnaire is a novel PREM designed to assess the user experience of TAI in both clinical and research settings. The instrument demonstrates good validity, acceptability and temporal stability, supporting its use as a reliable measure of patient experience.