title: Development and validation of a histological index for UC.
abstract: Although the Geboes score (GS) and modified Riley score (MRS) are commonly used to evaluate histological disease activity in UC, their operating properties are unknown. Accordingly, we developed an alternative instrument.
  
  
  
  Four pathologists scored 48 UC colon biopsies using the GS, MRS and a visual analogue scale global rating. Intra-rater and inter-rater reliability for each index and individual index items were measured using intraclass correlation coefficients (ICCs). Items with high reliability were used to develop the Robarts histopathology index (RHI). The responsiveness/validity of the RHI and multiple histological, endoscopic and clinical outcome measures were evaluated by analyses of change scores, standardised effect size (SES) and Guyatt's responsiveness statistic (GRS) using data from a clinical trial of an effective therapy.
  
  
  
  Inter-rater ICCs (95% CIs) for the total GS and MRS scores were 0.79 (0.63 to 0.87) and 0.80 (0.69 to 0.87). The correlation estimates between change scores in RHI and change score in GS and MRS were 0.75 (0.67 to 0.82) and 0.84 (0.79 to 0.88), respectively. The SES and GRS estimates for GS, MRS and RHI were: 1.87 (1.54 to 2.20) and 1.23 (0.97 to 1.50), 1.29 (1.02 to 1.56) and 0.88 (0.65 to 1.12), and 1.05 (0.79 to 1.30) and 0.88 (0.64 to 1.12), respectively.
  
  
  
  The RHI is a new histopathological index with favourable operating properties.
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Department of Medicine, University of Western Ontario, London, Ontario, Canada.|Department of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Mahmoud H
authors.initials: MH
authors.lastname: Mosli
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|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, Robarts Research Institute, 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, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, University of California San Diego, La Jolla, CA, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Sandborn
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Department of Gastroenterology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Geert
authors.initials: G
authors.lastname: D'Haens
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Department of Medicine, University of Western Ontario, London, Ontario, Canada.
authors.forename: Reena
authors.initials: R
authors.lastname: Khanna
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Shackelton
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Walker
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Nelson
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.
authors.forename: Margaret K
authors.initials: MK
authors.lastname: Vandervoort
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.
authors.forename: Valerie
authors.initials: V
authors.lastname: Frisbie
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Samaan
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Nuffield Department of Medicine, University of Oxford, Oxford, UK.|Oxford Clinical Trials Research Unit, University of Oxford, Oxford, UK.
authors.forename: Vipul
authors.initials: V
authors.lastname: Jairath
authors.affiliation: Department of Pathology, University of Western Ontario, London, Ontario, Canada.
authors.forename: David K
authors.initials: DK
authors.lastname: Driman
authors.affiliation: Department of Pathology, University Hospital of KU Leuven and UZ Gent, Leuven, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: Geboes
authors.affiliation: Department of Pathology, University of California, San Diego, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Valasek
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic Arizona, Scottsdale, USA.
authors.forename: Rish K
authors.initials: RK
authors.lastname: Pai
authors.affiliation: Massachusetss General Hospital, Boston, USA.|Department of Pathology, Harvard Medical School, Boston, USA.
authors.forename: Gregory Y
authors.initials: GY
authors.lastname: Lauwers
authors.affiliation: Department of Pathology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Riddell
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ontario, Canada.
authors.forename: Larry W
authors.initials: LW
authors.lastname: Stitt
authors.affiliation: Robarts Clinical Trials, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.|Division of Gastroenterology, University of California San Diego, La Jolla, CA, USA.
authors.forename: Barrett G
authors.initials: BG
authors.lastname: Levesque
mesh_terms: D000328:Adult; D001706:Biopsy; D003093:Colitis, Ulcerative / Q000473:pathology*; D003106:Colon / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013223:Statistics as Topic
keywords: HISTOPATHOLOGY; ULCERATIVE COLITIS