Representation and reporting of diverse groups in randomised controlled trials of pharmacological agents in inflammatory bowel disease: a systematic review

Inflammatory bowel disease (IBD) is now recognised as a global disease, with incidence rapidly increasing in newly industrialised countries in South America, Asia, and Africa. Trials in IBD, therefore, should adequately represent diverse groups with respect to gender, age, place of residence, race, and ethnicity to ensure the global applicability and generalisability of their findings. In this systematic review, we searched PubMed and Embase for randomised controlled trials (RCTs) published in English from Jan 1, 1995, to Jan 13, 2023, evaluating the efficacy of any pharmacological intervention in patients with IBD. Of 7543 records yielded in the search, we included 617 records reporting data from 627 RCTs and 108 986 participants. The results show a paucity of adequate representation of diverse groups in these RCTs. This finding was true for various groups, including racially and ethnically diverse populations, older (aged >65 years) and younger (aged <18 years) populations, those who identify outside of the gender binary, and people from South America and Africa. Also, some regions had an apparent scarcity of funding sources for trials. Pharmaceutical companies and clinical trial organisations should aim to ensure adequate representation of such under-represented groups in future IBD trials.