title: Prospective validation study of the International Classification of Functioning, Disability and Health score in Crohn's disease and ulcerative colitis.
abstract: OBJECTIVE
  Inflammatory bowel diseases (IBD) may result in disability. We aim to validate a novel scoring system for the IBD disability index (IBD-DI), and identify predictors of disability and its correlation with work absenteeism.
  
  
  METHODS
  This prospective IBD ambulatory clinic cohort study measured IBD-DI, Crohn's Disease Activity Index (CDAI) for Crohn's disease (CD) or partial Mayo score (pMayo) for ulcerative colitis (UC), IBDQ quality-of-life, and Work Productivity and Activity Impairment. Negative IBD-DI represented greater disability. Validation tests were performed and predictors and extent of work absenteeism were determined.
  
  
  RESULTS
  166 consecutive subjects were recruited (75 CD, 41 UC, 50 controls). IBD-DI correlated with CDAI (r=-0.77, P<0.001), pMayo (r=-0.82, P<0.001) and IBDQ (r=0.86, P<0.001). IBD-DI differentiated CD, and UC from controls (medians -7, -4, +10; P<0.001) with a score of >3.5 identifying controls with 94% sensitivity and 83% specificity (area-under-curve 0.92). Stable patients had unchanged IBD-DI (P=ns) but not in those who relapsed (P<0.001). Intraclass correlation was 0.89 and Cronbach's alpha of internal consistency was 0.94. Diagnosis age, sex, phenotype, perianal disease, prior surgery, steroid-use and disease duration did not influence the IBD-DI but active use of biological agents significantly reduced disability (P=0.03). 21.6% of IBD patients had moderate-severe disability equating to missing >25% of work hours in the previous week. Multivariate analysis identified that only IBD-DI to be predictive of unemployment status (OR: 0.94; 95% CI: 0.89-0.99).
  
  
  CONCLUSIONS
  The IBD-DI is a valid tool measuring disability in both CD and UC and correlates with workforce participation. It is a potential useful tool in the assessment of participation restriction and activity limitation.
  
  
  BACKGROUND
  ACTRN12613000903785.
authors.affiliation: Gastroenterology and Liver Services, Concord Hospital, Hospital Rd, Sydney, New South Wales 2139, Australia; Faculty of Medicine, The University of New South Wales, Sydney, Australia. Electronic address: rupertleong@outlook.com.
authors.forename: Rupert W L
authors.initials: RW
authors.lastname: Leong
authors.affiliation: Gastroenterology and Liver Services, Concord Hospital, Hospital Rd, Sydney, New South Wales 2139, Australia; Faculty of Medicine, The University of New South Wales, Sydney, Australia.
authors.forename: Tony
authors.initials: T
authors.lastname: Huang
authors.affiliation: Gastroenterology and Liver Services, Concord Hospital, Hospital Rd, Sydney, New South Wales 2139, Australia; Faculty of Medicine, The University of New South Wales, Sydney, Australia.
authors.forename: Yanna
authors.initials: Y
authors.lastname: Ko
authors.affiliation: Gastroenterology and Liver Services, Concord Hospital, Hospital Rd, Sydney, New South Wales 2139, Australia.
authors.forename: Ari
authors.initials: A
authors.lastname: Jeon
authors.affiliation: Gastroenterology and Liver Services, Concord Hospital, Hospital Rd, Sydney, New South Wales 2139, Australia; Faculty of Medicine, The University of New South Wales, Sydney, Australia.
authors.forename: Jeff
authors.initials: J
authors.lastname: Chang
authors.affiliation: Department of Rehabilitation Medicine, Braeside Hospital, Sydney, Australia; Faculty of Medicine, The University of New South Wales, Sydney, Australia.
authors.forename: Friedbert
authors.initials: F
authors.lastname: Kohler
authors.affiliation: Gastroenterology and Liver Services, Concord Hospital, Hospital Rd, Sydney, New South Wales 2139, Australia.
authors.forename: Viraj
authors.initials: V
authors.lastname: Kariyawasam
mesh_terms: D000041:Absenteeism; D000328:Adult; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000150:complications; D003424:Crohn Disease / Q000150:complications; D004185:Disability Evaluation; D004526:Efficiency; D004651:Employment; D005260:Female; D006801:Humans; D064702:International Classification of Functioning, Disability and Health; D008297:Male; D011446:Prospective Studies; D012372:ROC Curve; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
keywords: Colitis; Crohn's; Disability; Employment; Inflammatory bowel disease; Work