The Impostor Phenomenon Construct in Medical Education: A Meta-Analysis of its Prevalence and a Critical Appraisal of its Measurement

Impostor phenomenon (IP) is widely cited as a significant challenge in medical education, yet its conceptual and methodological foundations are unstablem, hindering a clear understanding of its true scope and impact. Thus, this systematic review and meta-analysis aimed to first establish a pooled prevalence of IP among medical students, and second, to critically appraise the measurement tools and definitions used in the literature. We systematically searched PubMed, Scopus, Web of Science, and CINAHL through July 2025 for all studies quantitatively assessing IP prevalence in medical students. Using a random-effects model, we analyzed data from 34 studies, including 9,550 participants. The overall pooled prevalence of IP was 49% (95% CI [0.43–0.54]), but this figure is complicated by extreme heterogeneity across studies (I ²  = 95.6%, P < 0.001) despite multiple sensitivity analyses. Subgroup analyses revealed significant prevalence differences by sex (females 51% vs. males 40%; P = 0.021), geographic region (P < 0.001), and the measurement tool used (P < 0.001). The qualitative synthesis suggested associations between IP and negative mental health outcomes, including anxiety, depression, and burnout. Nevertheless, the variance driven by different measurement tools suggests that researchers may not be consistently measuring the same construct. The reliance on unvalidated cutoffs further weakens the validity of prevalence estimates. We conclude that while IP is clearly a prevalent concern, the construct's weak theoretical grounding and inconsistent measurement impede meaningful progress. Advancing this area of medical education research requires a foundational shift toward conceptual clarity and methodological rigor.