Introduction Crohn’s Disease (CD) is a chronic, inflammatory, autoimmune disorder that substantially impairs patients’ physical and emotional well-being. Despite this there is no CD-specific patient-reported outcome measure (PROM) available for determining the efficacy of alternative interventions for the condition. The objective of the study is to develop and validate the first such patient-reported outcome measure. Questionnaire content was derived from 30 qualitative interviews conducted with UK CD patients. Cognitive debriefing interviews conducted with a new sample of 15 CD patients indicated that the draught scales were relevant, clear and easy to use.
Methods A test-retest postal survey was conducted to; identify the final scales, confirm their unidimensionality (by means of Rasch analysis) and to determine reproducibility and construct validity. A subset of the respondents was sent a second questionnaire package 2 weeks after completing the first. The package included the CLIQ, the Nottingham Health Profile (NHP), the Unidimensional Fatigue Impact Scale (U-FIS) and a demographic questionnaire.
Results The questionnaire package was completed by 273 CD patients (34.4% male; aged 16–79 (mean: 43.9; SD 15.1) years). Of these, 107 also completed the second package. Items were removed from the scales that misfit the Rasch model (Chi2 p > 0.05), were redundant or displayed differential functioning by gender. Rasch analysis confirmed two unidimensional scales (p < 0.05); activity limitations (11 items) and QoL (27 items). Internal consistency was good for both scales (0.93 and 0.91) as was test-retest reliability (0.89 and 0.91 respectively). The CLIQ scales were related (as expected) with the NHP section scores and the U-FIS. It was interesting to note that QoL scores were related to both physical and emotional impairments.
Conclusion The CLIQ is the first scientifically rigorous PROM designed specifically for CD patients. It consists of two unidimensional scales with excellent psychometric properties. It should prove to be a valuable tool for evaluating the impact of CD and its treatment from the patients’ perspective.
Disclosure of Interest None Declared
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.