PT  - JOURNAL ARTICLE
AU  - Mosli, Mahmoud H
AU  - Feagan, Brian G
AU  - Zou, Guangyong
AU  - Sandborn, William J
AU  - D'Haens, Geert
AU  - Khanna, Reena
AU  - Shackelton, Lisa M
AU  - Walker, Christopher W
AU  - Nelson, Sigrid
AU  - Vandervoort, Margaret K
AU  - Frisbie, Valerie
AU  - Samaan, Mark A
AU  - Jairath, Vipul
AU  - Driman, David K
AU  - Geboes, Karel
AU  - Valasek, Mark A
AU  - Pai, Rish K
AU  - Lauwers, Gregory Y
AU  - Riddell, Robert
AU  - Stitt, Larry W
AU  - Levesque, Barrett G
TI  - Development and validation of a histological index for UC
AID  - 10.1136/gutjnl-2015-310393
DP  - 2017 Jan 01
TA  - Gut
PG  - 50--58
VI  - 66
IP  - 1
4099  - http://gut.bmj.com/content/66/1/50.short
4100  - http://gut.bmj.com/content/66/1/50.full
SO  - Gut2017 Jan 01; 66
AB  - Objective 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.Design 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.Results 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.Conclusions The RHI is a new histopathological index with favourable operating properties.