Study	Reason for exclusion
Colombel 2001	Did not fit with our inclusion criteria: different patients. The study assessed the role of IL‐10 in preventing post‐operative recurrence of Crohn's disease
de Villiers 2003	Did not fit with our inclusion criteria: different patients. This was a selected summary of a study of IL‐10 in mice
Dejaco 1998	Did not fit with our inclusion criteria: different patients. In vivo study of patients with Crohn's disease or ulcerative colitis
Geier 2007	Review
Schreiber 2002	Editorial
Tilg 1998a	Non‐RCT
Tilg 1998b	Did not fit with our inclusion criteria: different outcomes of interest
Tilg 2002a	Did not fit with our inclusion criteria: different outcomes of interest
Tilg 2002b	Did not fit with our inclusion criteria: different outcomes of interest