The Impact of Specialization in Journal Networks and Scholarship

BACKGROUND: The use of bibliometrics to evaluate authors, institutions, and journals faces significant challenges in comparing biomedical specialties because of marked differences among fields. Our objective was to evaluate the effect of specialty field and physician numbers on bibliometric parameters. METHODS: For this bibliometric analysis, data from MDLinx.com and SClmago Journal & Country Rank for 2016 were used to rank the journals. The 2015 Physician Specialty Data Report provided the number of specialists in specific fields. We assessed the means for bibliometric parameters across medical and surgical specialties. RESULTS: A total of 904 journals within 25 medical and surgical specialties were identified. Medical specialty journals had higher average total citations than did surgical specialty journals (8360 +/- 16082 vs. 6217 +/- 8743; P = 0.01). Medical specialties with the highest impact factor were oncology (7.8 +/- 20.7), psychiatry (4.6 +/- 4.0), and neurology (4.4 +/- 4.1), whereas surgical specialties were led by urology (2.9 +/- 3.3), cardiothoracic surgery (2.9 +/- 2.7), and general surgery (2.6 +/- 1.7). Impact factor and Eigenfactor score (a measure of both journal citations and caliber) were strongly correlated (r = 0.84, P = 0.0001). Comparison of impact factor per total physicians in the specialty suggested that top-ranked specialty journals were in allergy/immunology, pulmonology, and cardiothoracic surgery. Mean Eigenfactor score per total physicians showed that top journals were in cardiothoracic surgery, rheumatology, and pulmonary medicine. CONCLUSIONS: Journal bibliometrics, which may strongly influence professional advancement and grant funding, show dramatic differences in ranking after accounting for specialty and physician population. Improved analysis and understanding of available bibliometrics, including their limitations, are necessary to appreciate their role in measuring scholarship.