Bibliometric evaluation of systematic review and meta analyses published in the top 5 "high-impact" radiology journals

Introduction: Meta-analyses provide high-level evidence and understanding their trends may provide understanding of the field as a whole. Bibliometric analysis was undertaken to understand research trends in a particular field or subfield and to assess citation as a measure of impact. Methods: All journals categorised as "Radiology, Nuclear Medicine & Medical Imaging" under the Web of Science subject category were included. After analyzing impact factors of the journals in up to 2018, the top five journals were identified. The retrieved results were ordered by citation count based on Web of Science and Scopus. Specific parameters regarding the title, journal, publication year, authors, country of origin, institution and university, field of study and funding sources were analyzed. Results: A total of 139 articles were identified. The mean number of citations per article was 25.3 and 22.6 in Scopus and Web of Science respectively, with four articles receiving 100 or more citations. European Radiology had the greatest number of top cited articles (n = 68; 49%). Most number of articles originated from South Korea (n = 60; 43%) and the commonest field of focus with the most common being oncology (n = 51; 27%). Conclusion: The top 5 high impact journals published a large number of meta-analysis and systematic reviews. The greatest number of top-cited articles were from South Korea, shifting away from the United States. Large number of studies focused on oncologic imaging, consistent with recent trends towards development of imaging biomarkers and personalized medicine. Author H index did not predict citation number or density.