Impact of Open Access on citations
“…a purposive sample of 4633 articles for the four subjects from high impact journals were examined, 2280 (49%) were [Open Access] and had a mean citation count of 9.04, whereas the mean for [non-Open Access] articles was 5.76…”
Norris, M., (2008). The citation advantage of open access articles.
“…Comparing [Open Access] and [non-Open Access] articles in the same journal/year, [Open Access] articles have consistently more citations, the advantage varying from 25%-250% by discipline and year….”
Hajjem, C., Harnad, S. and Gingras, Y. (2005) Ten-year cross-disciplinary comparison of the growth of Open Access and how it increases research citation impact. IEEE Data Engineering Bulletin, 28 (4) pp39-47.
Impact of Open Access articles vs non-Open Access articles published in the same journal:
Eysenbach, G. (2006). Citation Advantage of Open Access Articles, PLoS Biology, Volume 4, Issue 5, May 2006.
- In the first 4–10 months after publication: Open Access articles remained twice as likely to be cited than non-Open Access articles (odds ratio = 2.1 [1.5–2.9])
- After 10 to 16 months from publication: odds ratio increased to 2.9 (1.5–5.5)
"…When the authors looked just at poorer countries, however, they found that the influence of open access was more than twice as strong. For example, in Bulgaria and Chile, researchers cited nearly 20% more open access articles, and in Turkey and Brazil, the number of citations rose by more than 25%. Free online availability is not a huge driver of science in the first world, but it shapes parts of science in the rest of world …"
Dolgin, E., (2009). Online access = more citations, The Scientist, 19th February.
Back to the top
project tracks the current copyright conditions of the journal publishers. At time of writing over 60% of journals publishers allow pre-print or post-print archiving. Out of 581 publishers only 221 prevent you from uploading to a repository (link here for up-to-date statistics
and a publishers' list
“…Of the 328 publishers listed on SHERPA/RoMEO 58% allow postprint archiving without embargo…”
“…70% of publishers formally allow some form of self-archiving…”
“…The UK currently has 11% of the global repositories, Germany having 12% and the USA 28%...”
Authors and repository
“…Currently the overall fraction of authors self-archiving is estimated to be 39%...”
Swan, A. and Brown, S. (2004) Authors and Open Access Publishing, Learned Publishing, 7, pp219–224.
“…Of the eight research councils in RCUK, seven now have open access policies for their funded research outputs…”
Back to the top
2 June 2009