Most Placebo-Controlled Trials in Inflammatory Bowel Disease were Underpowered Because of Overestimated Drug Efficacy Rates: Results from a Systematic Review of Induction Studies.

BACKGROUND AND AIMS: Most pharmaceutical clinical trials for inflammatory bowel disease [IBD] are placebo-controlled and require effect size estimation for a drug relative to placebo. We compared expected effect sizes in sample size calculations [SSCs] to actual effect sizes in IBD clinical trials. METHODS: MEDLINE, EMBASE, CENTRAL and the Cochrane library were searched from inception to March 26, 2021, to identify placebo-controlled induction …