Abstract
BACKGROUND: The Comprehensive Basic Science Examination (CBSE) is a widely used tool in undergraduate medical education to assess foundational knowledge in basic sciences and predict future academic performance. Despite its increasing international adoption, the extent and nature of its implementation across diverse educational contexts remain unclear. OBJECTIVE: This scoping review aims to synthesize the available evidence on the global implementation of the CBSE, focusing on its characteristics, assessment approaches, reported outcomes, and limitations. METHODS: Following the Joanna Briggs Institute (JBI) methodology and PRISMA-ScR guidelines, five databases and gray literature sources were searched. Sixteen peer-reviewed studies conducted in six countries were included. The methodological quality of the studies was evaluated using the Medical Education Research Study Quality Instrument (MERSQI). RESULTS: The CBSE was used primarily in Iran, the United States, and South Korea, either as the standardized NBME version or as institution-specific adaptations. Most implementations were summative in nature, though formative and diagnostic approaches were also reported. The CBSE showed positive correlations with academic performance indicators such as GPA and licensing exam scores (e.g., USMLE Step 1, CPIE). However, limitations included resource constraints, variability in predictive validity, lack of alignment with curricula, and heterogeneous exam structures. The average methodological quality of the included studies was moderate. CONCLUSIONS: The CBSE is a promising assessment tool for evaluating medical students' basic science knowledge and predicting academic outcomes. However, its use and effectiveness vary significantly across contexts. To optimize its implementation, institutions should consider curricular alignment, resource availability, and local validation. Further high-quality, multicenter research is needed to enhance its applicability and reliability in global medical education. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40670-025-02503-8.