Developing a standard set of patient-centred outcomes for inflammatory bowel disease - an international, cross-disciplinary consensus by Kim, AH, Roberts, C, Feagan, BG, Banerjee, R, Bemelman, W, Bodger, K, Derieppe, M, Dignass, A, Driscoll, R, Fitzpatrick, R, Gaarentstroom-Lunt, J, Higgins, PD, Kotze, PG, Meissner, J, O'Connor, M, Ran, Z-H, Siegel, CA, Terry, H, van Deen, WK, van der Woude, CJ, Weaver, A, Yang, S-K, Sands, BE, Vermeire, S, Travis, SP