Hot on the heels of the UK Government’s move to re-shape the science publishing system by requiring publicly funded science research to be open-access from 2014, comes research to suggest the impact of research varies little between subscriber-only and open access journals.
The paper*, published today in BMC Medicine used citation rates and measures of “impact factor” of papers in both open access and subscription-based to see which are more widely cited and are therefore deemed to have greater impact.
The researchers, Bo-Christer Björk from Hanken School of Economics, Helsinki, and David Solomon from Michigan State University, both founded open access journals in the 1990s. They compared the impact factors of 610 open access journals and over 7000 subscription journals and found:
The citation rate for subscription journals was overall 30% higher than for open access ones but this difference was largely due to a high share of older OA journals, particularly from regions like Latin America in the citation indexes. When like was compared with like, for instance, journals founded after 2000 from difference regions or disciplines, the differences disappeared.
So for the last decade of publishing, open access journal papers are cited at about the same rate as subscription journals, suggesting their impact is similar. The research would appear to discount the notion that open access papers are somehow inferior to those published in subscription-based journals. Most scientists already knew that, but nice to see some research on it at a time when the open access movement has reached a watershed moment – at least as far as the UK is concerned.
Background: In the past few years there has been an ongoing debate as to
whether the proliferation of open access (OA) publishing would damage the
peer review system and put the quality of scientific journal publishing at risk.
Our aim was to inform this debate by comparing the scientific impact of OA
journals with subscription journals, controlling for journal age, the country of
the publisher, discipline and (for OA publishers) their business model.
Methods: The 2-year impact factors (the average number of citations to the
articles in a journal) were used as a proxy for scientific impact. The Directory
of Open Access Journals (DOAJ) was used to identify OA journals as well as
their business model. Journal age and discipline were obtained from the
Ulrich’s periodicals directory. Comparisons were performed on the journal
level as well as on the article level where the results were weighted by the
number of articles published in a journal. A total of 610 OA journals were
compared with 7,609 subscription journals using Web of Science citation data
while an overlapping set of 1,327 OA journals were compared with 11,124
subscription journals using Scopus data.
Results: Overall, average citation rates, both unweighted and weighted for
the number of articles per journal, were about 30% higher for subscription
journals. However, after controlling for discipline (medicine and health versus
other), age of the journal (three time periods) and the location of the publisher
(four largest publishing countries versus other countries) the differences
largely disappeared in most subcategories except for journals that had been
launched prior to 1996. OA journals that fund publishing with article
processing charges (APCs) are on average cited more than other OA
journals. In medicine and health, OA journals founded in the last 10 years are
receiving about as many citations as subscription journals launched during the
Conclusions: Our results indicate that OA journals indexed in Web of
Science and/or Scopus are approaching the same scientific impact and
quality as subscription journals, particularly in biomedicine and for journals
funded by article processing charges