In addition, a complementary electronic search with the following algorithm was used: (“inflammatory bowel disease” OR “ulcerative colitis” OR Crohn) AND (anti-TNF OR antiTNF OR infliximab OR adalimumab OR certolizumab OR golimumab) AND (vedolizumab OR ustekinumab OR tofacitinib) AND (metaanalysis OR meta-analysis OR “systematic review”). Here, TNF is linked to inflammatory bowel disease.