Intra-Specialty Citation Pattern in Radiology and Gastroenterology/Hepatology Journals: A Cross-Specialty Comparison.

To investigate intra-specialty citation patterns of radiology articles, compared with another medical specialty: gastroenterology/hepatology. Four radiology journals (, , , ) and four gastroenterology/hepatology journals () with similar Web of Science in-category 2020 IF ranking were selected. The original research, review, letter, and editorial articles published in these journals in 2021 were identified. The average number of intra-specialty citations per article (intra-specialty citation ) and percentage of intra-specialty citations out of total citations per article (intra-specialty citation ) were compared between radiology and gastroenterology/hepatology articles using Student's -test. The radiology articles demonstrated a lower total citation count per article (radiology: 29.7 ± .4 (mean ± SEM), n = 2063; gastroenterology/hepatology: 50.1 ± 1.4, = 1335). The citation was also lower in radiology articles than gastroenterology/hepatology articles (radiology: 12.9 ± .2, gastroenterology/hepatology: 19.6 ± .7; < .001), both overall and in all article types. Additionally, the overall citation was not significantly different between the two specialties (radiology: 48.8% ± .5%; gastroenterology/hepatology: 47.1 ± .8%; = .057), although the intra-specialty citation were higher in radiology original research and editorial article types. The significantly lower per-article intra-specialty citation in all radiology article types, a measurement that directly links to specialty IFs, may contribute to the lower impact factors of radiology journals compared with gastroenterology/hepatology ones.