The aim of this nationwide cross-sectional study was to create and substantiate the Crohn’s Disease–Health Index (CD-HI) for systematically assessing the burden of symptoms in those struggling with Crohn’s disease.

The study involved adults diagnosed with Crohn’s disease in order to identify the most prevalent and impactful symptoms of the disease. The identified symptoms were incorporated into the CD-HI. Subsequently, factor analysis, qualitative interviews with patients, evaluation of test-retest reliability, and known group validity testing were utilized for refining and validating the CD-HI.

The CD-HI comprised twelve subscales that holistically captured the burden of Crohn’s disease from the patient's perspective. Beta testing encompassing fifteen patients indicated that the instrument was user-friendly, clear, and relevant. Evaluation of test-retest dependability with twenty-three patients depicted high dependability across individual questions, subscales, and the full instrument (for the full instrument, the intraclass correlation coefficient was 0.84). Furthermore, the CD-HI and its subscales displayed strong internal consistency (Cronbach's α = 0.98 for the full instrument) and adequately differentiated between groups of patients with varying levels of illness severity.

This study underscored CD-HI as a reliable, valid, sensitive, and pertinent disease-specific patient-reported outcome measure for examining the multifaceted burden of Crohn’s disease. It also highlighted its utility in evaluating the effectiveness of future Crohn’s disease therapies and supporting claims in drug labeling.