The role of centralized reading of endoscopy in a randomized controlled trial of mesalamine for ulcerative colitis by Travis, S, Feagan, B, Sandborn, W, D'Haens, G, Pola, S, McDonald, J, Rutgeerts, P, Munkholm, P, Mittmann, U, King, D, Wong, C, Zou, G, Donner, A, Shackleton, L, Gilgen, D, Nelson, S, Vandervoort, M, Fahmy, M, Loftus Jr., E, Panaccione, R, Assche, G, Vermeire, S, Levesque, B