Background: Journal impact factor (JIF) is a bibliometric proxy of relative journal importance. Mean dermatology JIF has nearly doubled since 1997. The reasons behind the increase have not been previously explored. Objective: To assess factors contributing to rising dermatology JIF. Methods: This bibliometric study utilized publicly-available citation and JIF data from the Thomson-Reuters InCites Journal Citation Reports "Dermatology and Venereology" category, from 1997-2017. Results: From 1997-2017, aggregate dermatology JIF increased by 70%, associated with a 64% increase in JIF numerator (total journal citations) and a 3% decrease in JIF denominator (total journal articles and reviews). In the four highest-JIF journals (JAAD, JAMA Dermatology/Archives of Dermatology, JID, and BJD), there was an increase in citations coming from non-dermatology specialty journals, including oncology, rheumatology, and multidisciplinary sciences. Journal impact factor was positively correlated with five JIF alternatives. Immediacy Index, a reflection of how fast dermatology journals are cited, increased four-fold (P<0.001). Limitations: Impact factor numerator/denominator data were not available before 1999. Conclusions: The nearly two-fold rise in dermatology JIF from 1997-2017 was associated with increased citations, an increasing proportion of which came from non-dermatology journals. This may reflect growing influence of dermatology research within both dermatology and other fields of medicine
