Development and content validation of patient-reported outcomes tools for ulcerative colitis and Crohn's disease in adults with moderate-to-severe disease

Background Ulcerative colitis (UC) and Crohn's disease (CD) are associated with a range of symptoms that adversely affect health-related quality of life. This research aimed to develop and validate two patient-reported outcome (PRO) tools to assess signs and symptoms in patients with moderate-to-severe UC or CD. Methods PRO-UC and PRO-CD Diaries were developed in accordance with US Food and Drug Administration (FDA) recommendations. Data were collected from concept elicitation interviews (in which patients described their symptoms and experience of the disease) and further refined through cognitive interviews (in which patients assessed the relevance and clarity of questions in the tools). Results Interviews were conducted with 12 patients for each indication. Five symptoms (urgent bowel movements, abdominal pain, frequent bowel movements, bloody stools, diarrhea/watery stools) were reported by 83-100% of participants with UC and were included in the final 6-item PRO-UC Diary: stool frequency, rectal bleeding (2 items), diarrhea, rectal urgency, and abdominal pain. For CD, seven symptoms (abdominal pain, diarrhea/loose stools, urgent bowel movements, fatigue/tiredness/weakness, frequent bowel movements, bloody stools, nausea) were reported by 50-100% of participants. These, together with vomiting and incontinence (reported by 42% and 33% of participants, respectively), were included in the final 10-item PRO-CD Diary, covering abdominal pain (2 items), stool frequency, liquid/very soft stool frequency, rectal bleeding, rectal urgency, nausea, vomiting, bowel incontinence, and general well-being. Symptoms were consistently cited across both indications to have an impact on quality of life, with frequent complaints being the need to always be near a toilet and inability to leave home, as well as general pain, discomfort, and nausea. For both tools, questions were accurately interpreted, with at least 67% of participants in both indications stating that items were easy to answer/relevant to their condition and symptoms were easy to recall over the last 24 h. Conclusions Both the PRO-UC and PRO-CD Diaries were developed and validated in accordance with FDA recommendations, providing two new tools for use in clinical trials to assess response to treatment in patients with UC or CD. Psychometric analyses are warranted to fully evaluate their properties and value for use in clinical trials.