Validation of the IBD-Control Questionnaire across different sociodemographic and clinical subgroups: secondary analysis of a nationwide electronic survey

Gerum G Gebeyehu; Frederick Taylor; Liz Dobson; J R Fraser Cummings; Stuart Bloom; Nicholas A Kennedy; Paul Christiansen; Keith Bodger

doi:10.1093/ecco-jcc/jjad147

Validation of the IBD-Control Questionnaire across different sociodemographic and clinical subgroups: secondary analysis of a nationwide electronic survey

J Crohns Colitis. 2024 Feb 26;18(2):275-285. doi: 10.1093/ecco-jcc/jjad147.

Authors

Gerum G Gebeyehu¹, Frederick Taylor^{1

2}, Liz Dobson², J R Fraser Cummings³, Stuart Bloom⁴, Nicholas A Kennedy⁵, Paul Christiansen⁶, Keith Bodger^{1

7}

Affiliations

¹ Department of Health Data Science, Institute of Population Health, University of Liverpool, Liverpool, UK.
² IBD Registry Ltd, London, UK.
³ Department of Gastroenteroogy, University Hospitals Southampton, Southampton, UK.
⁴ Department of Gastroenterology, University College London Hospitals NHS Foundation Trust, London, UK.
⁵ Exeter Inflammatory Bowel Disease Research Group, University of Exeter, Exeter, UK.
⁶ Department of Psychology, Institute of Population Health, University of Liverpool, Liverpool, UK.
⁷ Aintree University Hospital, Liverpool University Hospital Foundation Trust, Liverpool, UK.

Abstract

Background: The IBD-Control Questionnaire is a simple, generic measure of patient-perceived disease control used increasingly in clinical practice and research. We aimed to address knowledge gaps in its psychometric performance, to ensure that it can be used with confidence in a variety of contexts.

Methods: We analysed 7341 responses to the IBD Registry COVID-19 survey, sent to 40 911 patients who completed an online self-assessment tool during the pandemic. Questions covered demographics, comorbidities, inflammatory bowel disease [IBD] sub-type, and IBD-Control Questionnaire and symptom scores [CD-PRO2 or UC-PRO2]. Psychometric properties of IBD-Control-8 were tested overall and within subgroups (Crohn's disease [CD], ulcerative colitis [UC] and IBD unclassified; male and female; ≤65 and >65 years; number of co-morbidities; deprivation status).

Results: Internal consistency was very strong overall [α: 0.84, ω: 0.89] and for each subgroup [α range: 0.81-0.85; ω: 0.86-0.90]. Construct validity was demonstrated by moderate correlation of each item with global rating [VAS] [rs range: 0.47-0.65], strong correlation between IBD-Control-8 score and VAS [rs = 0.74], moderate-to-strong with PRO2 scores [CD: rs = -0.718; UC: rs = -0.602] and significantly higher IBD-Control-8 scores for PRO2-remission vs PRO2-active, consistent across subgroups. Exploratory and confirmatory factor analyses demonstrated a two-factor model (items loading onto 'Health-related Quality of Life' [HRQoL] or 'Treatment' domains). Extensive tests for factorial invariance confirmed consistency.

Conclusions: IBD-Control-8 is a psychometrically robust scale which can be used across a range of populations. It offers a quick, reliable, and valid method of assessing patient-perceived control. The construct of 'control' includes traditional HRQoL and a novel domain relating to treatment perception.

Keywords: Inflammatory bowel disease; patient-reported outcome measures.

MeSH terms

Colitis, Ulcerative* / drug therapy
Crohn Disease* / drug therapy
Female
Humans
Inflammatory Bowel Diseases* / diagnosis
Inflammatory Bowel Diseases* / epidemiology
Male
Quality of Life
Severity of Illness Index
Surveys and Questionnaires

Supplementary concepts

Inflammatory Bowel Disease 8

Grants and funding

IBD Registry Ltd