Qualitative Assessment of the Symptoms and Impact of Pancreatic Exocrine Insufficiency (PEI) to Inform the Development of a Patient-Reported Outcome (PRO) Instrument

BACKGROUND: Pancreatic exocrine insufficiency (PEI) affects patients with chronic pancreatitis (CP) and cystic fibrosis (CF) who produce insufficient digestive pancreatic enzymes. Common symptoms include steatorrhoea, diarrhea, and abdominal pain. OBJECTIVE: The objective of the study was to develop and test the content validity of a patient-reported outcome (PRO) instrument assessing PEI symptoms and their impact on health-related quality of life. METHODS: Instrument development was supported by a literature review, expert physician interviews (n = 10: Germany 4, UK 3, France 3), and exploratory, qualitative, concept-elicitation interviews with patients with CF and CP with PEI (n = 61: UK 29, Germany 18, France 14) and expert physicians (n = 10). Cognitive debriefing of the draft instrument was then performed with patients with PEI (n = 37: UK 24, Germany 8, France 5), and feasibility was assessed with physicians (n = 3). For all interviews, verbatim transcripts were qualitatively analysed using thematic analysis methods and Atlas.ti computerized qualitative software. All themes were data driven rather than a priori. RESULTS: Patient interviews elicited symptoms and impacts not reported in the literature. Six symptom concepts emerged: pain, bloating, bowel symptoms, nausea/vomiting, eating problems, and tiredness/fatigue. Six impact domains were also identified. A 45-item instrument was developed in English, French, and German for testing in cognitive debriefing patient interviews. Following cognitive debriefing, 18 items were deleted. CONCLUSION: Rigorous qualitative patient research and expert clinical input supported development of a PEI-specific PRO with the potential to aid management and monitoring of unmet needs among patients with PEI. The next step is to perform psychometric evaluation of the resulting instrument.