ObjectiveTo analyze the research hotspots and development trends of core outcome set (COS) from 2015 to 2024, providing a reference for future research in this field. MethodsWe retrieved literature on COS research from the Web of Science Core Collection and CNKI spanning January 1, 2015 to December 31, 2024. We extracted and organized data on the number of publications, journals, citation frequency, and keywords using Excel 2021. We performed keyword clustering analysis using VOSviewer 1.6.13 and generated strategic coordinate maps using Bibliometrix 3.13 in R 4.3.1. ResultsWe included a total of 1 288 studies, comprising 1 085 English publications and 203 Chinese publications. From 2015 to 2024, the number of COS publications showed a steady increase. English journals covered a wide range of fields, while Chinese journals were mainly focused on traditional Chinese medicine. High-impact articles primarily focused on COS methodology. Chinese literature mainly concentrated on the application of COS in traditional Chinese medicine, while English literature focused on child health, Delphi surveys, quality of life, and pain. The results of the strategic coordinate map showed that research on acupuncture core outcome indicators, qualitative studies of surgical COS, and Delphi-based COS for quality of life in patients with rheumatoid diseases were relatively weak, with significant room for improvement. ConclusionOver the past decade, COS research has shown a steady growth trend and has gradually become an important tool for improving the standardization and scientific rigor of clinical research. As COS research continues to expand, there is increasing overlap in the scope and findings of different studies. Future research could incorporate umbrella and basket study designs to optimize resource utilization and promote the application of COS in clinical practice.