title: Responsiveness of Endoscopic Indices of Disease Activity for Crohn's Disease.
abstract: OBJECTIVE
  The Crohn's Disease Endoscopic Index of Severity (CDEIS) and the Simple Endoscopic Score for Crohn's Disease (SES-CD) are commonly used to assess Crohn's disease (CD) activity; however neither instrument is fully validated. We evaluated the responsiveness to change of the SES-CD and CDEIS using data from a trial of adalimumab, a drug therapy of known efficacy.
  
  
  METHODS
  Paired video recordings (N=112) of colonoscopies (baseline and week 8-12) obtained from patients with CD who participated in a trial of adalimumab therapy were reviewed in random order, in duplicate, by four central readers (56 pairs of videos by 2 groups of readers). Responsiveness of the SES-CD and the CDEIS was evaluated by comparing correlations between the observed and pre-specified predictions of change scores for these endoscopic indices with a global endoscopic evaluation of severity (GELS), a patient reported outcome (PRO2), and the Crohn's disease activity index (CDAI), and by calculation of the standardized effect size, and Guyatt's Responsiveness statistic (GRS) using 2 definitions of change; (1) treatment assignment and (2) an absolute change in total PRO2 of 50. The potential application of effect size estimates was demonstrated by calculating hypothetical sample sizes for comparing two independent groups. The impact of removing stenosis as an index item and adjusting for the number of segments observed was also assessed.
  
  
  RESULTS
  Changes in both endoscopic instruments and the GELS were highly correlated. The SES-CD displayed numerically higher effect sizes for both definitions of change. The standardized effect size and GRS estimates (95% confidence interval) for the SES-CD based on treatment assignment were 0.84 (0.53, 1.15) and 0.79 (0.48, 1.09). Corresponding values for the CDEIS were 0.72 (0.42, 1.02) and 0.75 (0.45, 1.06). The standardized effect size and GRS estimates for the SES-CD based on an absolute change in total PRO2 of 50 points or greater were 0.76 (0.49, 1.02) and 0.93 (0.64, 1.21). Corresponding values for CDEIS were 0.70 (0.44, 0.97), 0.83 (0.55, 1.10). Removal of stenosis as an index item and adjusting for observed segments did not improve responsiveness estimates.
  
  
  CONCLUSIONS
  Although both the SES-CD and CDEIS are valid measures of endoscopic disease activity that are moderately responsive to changes in endoscopic disease activity, the SES-CD displayed numerically greater responsiveness in this data set.
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, Department of Medicine, University of Western Ontario, London, Ontario, Canada.
authors.forename: Reena
authors.initials: R
authors.lastname: Khanna
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ontario, Canada.
authors.forename: GuangYong
authors.initials: G
authors.lastname: Zou
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.
authors.forename: Larry
authors.initials: L
authors.lastname: Stitt
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, Department of Medicine, University of Western Ontario, London, Ontario, Canada.|Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ontario, Canada.
authors.forename: Brian G
authors.initials: BG
authors.lastname: Feagan
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, University of California San Diego, La Jolla, California, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Sandborn
authors.affiliation: Department of Gastroenterology, University Hospital Gasthuisberg, Leuven, Belgium.
authors.forename: Paul
authors.initials: P
authors.lastname: Rutgeerts
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.
authors.forename: John W D
authors.initials: JWD
authors.lastname: McDonald
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.
authors.forename: Elena
authors.initials: E
authors.lastname: Dubcenco
authors.affiliation: Digestive Health Center of Michigan, Chesterfield, Michigan, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Fogel
authors.affiliation: Inflammatory Bowel Disease Clinic, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Remo
authors.initials: R
authors.lastname: Panaccione
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, Department of Medicine, University of Western Ontario, London, Ontario, Canada.|Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ontario, Canada.|Nuffield Department of Medicine, University of Oxford, Oxford, UK.
authors.forename: Vipul
authors.initials: V
authors.lastname: Jairath
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Nelson
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Shackelton
authors.affiliation: AbbVie, Inc, North Chicago, Illinois, USA.
authors.forename: Bidan
authors.initials: B
authors.lastname: Huang
authors.affiliation: Nuffield Department of Medicine, University of Oxford, Oxford, UK.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: AbbVie, Inc, North Chicago, Illinois, USA.
authors.forename: Anne M
authors.initials: AM
authors.lastname: Robinson
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, University of California San Diego, La Jolla, California, USA.
authors.forename: Barrett G
authors.initials: BG
authors.lastname: Levesque
authors.affiliation: Robarts Clinical Trials, University of Western Ontario, London, Ontario, Canada.|Inflammatory Bowel Disease Centre, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Geert
authors.initials: G
authors.lastname: D'Haens
mesh_terms: D000068879:Adalimumab / Q000008:administration & dosage*; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage; D003424:Crohn Disease / Q000175:diagnosis / Q000188:drug therapy; D016903:Drug Monitoring / Q000379:methods / Q000706:statistics & numerical data; D016099:Endoscopy, Gastrointestinal / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012107:Research Design / Q000592:standards*; D018401:Sample Size; D012720:Severity of Illness Index; D013223:Statistics as Topic; D014741:Video Recording / Q000379:methods
chemical_list: D000893:Anti-Inflammatory Agents; D000068879:Adalimumab