Validity and Reliability of a Novel Multimodal Questionnaire for the Assessment of Abdominal Symptoms in People with Cystic Fibrosis (CFAbd-Score).

Background And Objective: For people with cystic fibrosis, validated patient-reported outcome measures for the assessment of the complex abdominal involvement are lacking. The objective of this study was to examine whether the CFAbd-Score, a novel questionnaire consisting of 28 items, meets the essential requirements (validity and reliability) for a patient-reported outcome measure according to US Food and Drug Administration recommendations.

Methods: Content validity was assessed by recording the frequencies and severity of symptoms that occurred during the prior 2 weeks in patients with cystic fibrosis (n = 116; aged ≥ 6 years).