Faecal incontinence core outcome set: an international Delphi consensus exercise among patients, health-care professionals, and researchers

Faecal incontinence is a debilitating anorectal disorder that can severely affect a person's quality of life. The variability in reported outcomes in studies on treatments for faecal incontinence complicates the synthesis of evidence, thereby weakening treatment recommendations. Furthermore, the emphasis on clinical outcomes often neglects outcomes that are crucial to patients' daily lives. Incorporating diverse stakeholder perspectives, we aimed to develop a core outcome set (COS)—a minimum set of outcomes that should be measured in future studies evaluating the efficacy of a treatment in adults with faecal incontinence. Following guidelines from the COMET initiative, this study proceeded through three steps: identifying outcomes via patient interviews and a systematic literature review; ranking and refining outcomes through two rounds of Delphi surveys involving patients, health-care professionals, and researchers; and finalising the COS through a consensus meeting with relevant stakeholders. Round 1 of the Delphi survey included 109 participants (73 health-care professionals and researchers and 36 patients) and round 2 involved 74 participants (54 and 20, respectively). In both rounds, participants ranked the importance of potential outcomes on a 9-point Likert scale. Of the 58 outcomes that entered round 1 and the three that were later added, 27 outcomes were voted out and the remaining 34 were discussed during a consensus meeting to finalise the COS. The final COS encompasses 13 outcomes: seven quality of life-related outcomes (quality of life, influence on daily activities, social functioning, treatment satisfaction, enjoyment in life, embarrassment, and peace of mind) and six clinical outcomes (severity of faecal incontinence, number of faecal incontinence episodes, urgency, stool consistency, adverse events, and adherence to therapy). This study establishes what outcomes should be included in a COS for use in faecal incontinence research, but future research is needed to identify the appropriate measurement instruments for each outcome and to establish appropriate timing for their assessment, which will further refine outcome definitions before this COS can be implemented. Once these aspects are clarified, the COS can be adopted into faecal incontinence research, which we hope will ultimately improve clinical care.