3. High Impact Journals and Open Access Uptake

3.1. Evidence Supporting Increased Citation Rates for Open Access Papers

OpCit – Reference Linking and Citation Analysis for Open Archives was a three-year research and development project completed at the end of 2002.  The project was funded by the Joint NSF – JISC International Digital Libraries Research Programme, and Open Access champion Stevan Harnad was the principal investigator.  One of project aims was to compile a bibliography of studies on ‘The effect of open access and downloads ('hits') on citation impact'.  One of the participants in the project, another Open Access advocate Steve Lawrence, concluded in his research carried out for OpCit that,

Free online availability facilitates access in many ways, including provision of online archives; direct connections among scientists or research groups; hassle-free links from e-mail, discussion groups and other services; indexing by web search engines; and the creation of third-party search services.  Free online availability of scientific literature offers substantial benefits to science and society.  To maximize impact, minimize redundancy and speed scientific progress, authors and publishers should aim to make research easy to access.  [Lawrence, S., ‘Free online availability substantially increases a paper's impact’, Nature, 31 May 2001]

The top five most-cited papers (as measured by Google Scholar) from this bibliography of work studying the impact of Open Access on citation rates are listed below if you are interested in reading more on the topic:

1. Lawrence, S., ‘Free online availability substantially increases a paper's impact, Nature, 31 May 2001. Metrics: GS, Biblio

2. Harnad, S. and Brody, T., ‘Comparing the Impact of Open Access (OA) vs. Non-OA Articles in the Same Journals, D-Lib Magazine, Vol. 10 No. 6, June 2004. Metrics: GS, Biblio

3. Antelman, K., ‘Do Open-Access Articles Have a Greater Research Impact?College and Research Libraries, 65(5):372-382, September 2004. Metrics: GS, Biblio

4. Eysenbach, G., ‘Citation Advantage of Open Access Articles, PLoS Biology, Volume 4, Issue 5, May 2006. Metrics: GS, Biblio

5. Harnad, S., et al., ‘The Access/Impact Problem and the Green and Gold Roads to Open Access: An Update’, Serials Review, Vol. 34, No. 1, March 2008, 36-40. Metrics: GS, Biblio

The overall conclusion of this research was that, free open access to articles creates higher citation rates for those papers and that free and open dissemination of research output increases the reputation of a researcher and opens channels for communication and collaboration, which benefits everyone.


Key Perspectives are consultants in scholarly communication; they have produced reports, briefings, and presentations on the impact of Open Access on scholarly communications.  The slides below are taken from one of their presentations on the impact of Open Access on citation rates.  The graphics show why the majority of researchers want to publish their work and how Open Access increases citation rates in different subject areas:

Key Perspectives graph

When researchers were asked why they published/wanted to publish their work, the majority of those who participated in the study said that they published/wanted to publish their work 'to communicate results to peers'.  As studies show that Open Access to research output increases citation rates, it then follows that the most successful way of communicating results to peers is by publishing papers not necessarily in journals with high impact factors, journals that may not be Open Access, but by publishing them in an Open Access publication or platform.  This makes the paper accessible to everyone and increases dissemination of research results, which is why researchers publish in the first place.


PLoS - the Public Library of Science has published many research articles which show that Open Access papers attract higher citation rates.  A research paper in PLoS One, ‘Self-Selected or Mandated, Open Access Increases Citation Impact for Higher Quality Research’, is co-authored by Open Access champion Stevan Harnad.  The paper includes many tables and graphics charting the impact advantage of Open Access and claims that, authors who self-archive even their own final drafts of papers to make them freely accessible have an advantage over other authors publishing in the same journal: these self-archived Open Access papers are cited significantly more than articles in the same journal.  The research concludes that,

The OA advantage is greater for the more citable articles, not because of a quality bias from authors self-selecting what to make OA, but because of a quality advantage, from users self-selecting what to use and cite, freed by OA from the constraints of selective accessibility to subscribers only.  It is hoped that these findings will help motivate the adoption of OA self-archiving mandates by universities, research institutions and research funders.  [Harnad, S., et al. ‘Self-Selected or Mandated, Open Access Increases Citation Impact for Higher Quality Research’, PLoS ONE, 5(10), 2010]

Another research paper published in PLoS Biology on this subject is 'Citation Advantage of Open Access Articles' by Gunther Eysenbach.  The author compared the impact of Open Access and non-Open Access articles from the same journal in the first 4–16 months after their publication and found out that Open Access articles are cited earlier and are, on average, cited more often than non-Open Access articles.  He concludes that 'Researchers, publishers, and policymakers confronted with the question of whether or not to invest in OA publishing have reason to believe that OA accelerates scientific advancement and knowledge translation of research into practice.'  [Eysenbach, G. 'Citation Advantage of Open Access Articles', PLoS Biology, 4(5), 2006.]