Study	Reason for exclusion
Blonski 2011	This study sought to identify factors predictive of endoscopic and clinical disease course No validation was performed
Hameed 2001	This study evaluated whether clinical presentation correlates with endoscopic findings The Baron Score was used to assess endoscopic disease activity It is unclear whether a scoring instrument was used to assess clinical disease activity Study published in abstract form only
Kato 2011	This retrospective analysis aimed to determine whether there is discrepancy between sigmoidoscopy and colonoscopy in the examination of patients with UC using the Mayo score No validation was performed
Neumann 2012	This is a review article that discusses findings from Samuel 2013
Ohkusa 2006	This study does not report on endoscopic scoring index validation testing results
Powell‐Tuck 1982	No estimates of correlation reported
Travis 2009	This study describes the development of the UCEIS There was no validation of the UCEIS performed
Travis 2011	This study describes the development of the UCEIS There was no validation of the UCEIS performed While inter‐ and intra‐observer variability was calculated for the Baron Score during the model development phase, correlation estimates are given for individual items, not the overall Baron Score

UCEIS: Ulcerative Colitis Endoscopic Index of Severity