Funding of Radiology Research:Frequency and Association With Citation Rate

OBJECTIVE. The purpose of this study is to investigate the frequency of funded research published in major radiology journals and to determine whether funding is associated with the article citation rate.MATERIALS AND METHODS. A total of 600 consecutive original research articles published in three journals-AJR, Radiology, and European Radiology-were included. Linear regression analysis was performed to determine the association between research funding and the article citation rate, as adjusted for journal, continent of origin of the first author, subspecialty, study findings included in the article title, number of authors, immediate open access publication, and time since publication online.RESULTS. Funding was declared for 286 of 600 included articles (47.7%). Sources of funding were as follows: federal sponsorship (29.4%), a nonprofit foundation (16.4%), both federal sponsorship and a nonprofit foundation (16.1%), private industry (10.1%), intramural institutional research funding (9.8%), and other funding sources (18.2%). Articles with first authors whose continent of origin was Europe (p <0.001), vascular and interventional radiology articles (p <0.001), and articles published in AJR (p <0.001) were significantly more frequently unfunded than funded. Articles published in Radiology were significantly more frequently funded (p <0.001). The citation rate was not significantly different between funded and unfunded articles (p = 0.166). In adjusted linear regression analysis, funding was not significantly associated with the citation rate (beta coefficient,- 0.31; 95% CI,-3.27 to 2.66; p = 0.838).CONCLUSION. Almost half of the research articles published in major radiology journals declared funding, a proportion that has increased compared with findings from previous studies (17% of articles in a study from 1994 and 26.9% of articles in a study of literature published between 2001 and 2010). Most funded articles received support from federal sponsors or nonprofit foundations, whereas only a minority of funded articles were supported by private industry. Funding was not associated with a higher citation rate.