Background Widening participation to health science degrees is a vital part of our efforts to ensure a high-quality pool of graduates in clinical fields. With the increasing usage of multiple mini interviews for selection to these courses, it is crucial that we recognise the biases within these selection processes. Aims This paper aims to examine recently published literature to determine the extent to which demographic factors (age, race, sex and socioeconomic background) impact on MMI scores for applicants to health science degrees. Methods A literature search was conducted using the Medline and SCOPUS databases for literature published from 2015 to present. Relevant papers were identified through a Boolean search, and individually analysed to determine their relevance to this review. Results This review identified nine relevant papers. Biases were identified in all four domains, but the evidence was mixed and of varying quality. The strongest evidence for a bias was found in papers looking at socioeconomic background. Conclusion Further research is required to determine the extent to which the MMI approach is biased against certain groups of applicants, and to identify ways to address these imbalances, as evidence of the impact of demographics on MMI score has been identified.