Open access, where scientists pay a fee to publish so that the public and other scientists can read the study for free, is a negligible issue to most scientists, according to a new research report in The FASEB Journal.
In the report, Philip M. Davis from Cornell University says that open access open access leads to increases in downloads, but not to increases in citations (their use), a key factor used in scientific publishing to assess a research article's relative importance and value. He believes the study will help scientists make informed decisions about where they publish their work and assist governments, granting institutions and universities with evaluating whether or not their open access policies are leading to greater dissemination of useful scientific knowledge.
"The widely-accepted 'open access citation advantage' appears to be spurious," said Davis. "There are many benefits to the free access of scientific information, but a citation advantage doesn't appear to be one of them."
To reach his conclusions, Davis ran several parallel randomized controlled trials. Upon publication, articles, including those from The FASEB Journal, were randomly assigned to either the open access or the subscription-access group. He then observed how these articles performed in terms of downloads and citations over three years.
He found that free access did not affect the number of citations a paper received, rejecting a widely-held belief that open access articles are cited more frequently because of their free-access status. The results are consistent over time across 36 journals covering the sciences, social sciences and humanities.
"A study like this is long overdue," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. "For years, institutions and organizations have promoted 'open access' policies under the assumption that some scientists cannot gain access to research reports because they or their institutions have to pay for subscriptions. Now we learn that 'open access' articles may be seen by more, but not cited (used) by more fellow scientists. It's probably time to drop the 'open access advantage' assumption and policies that follow from it."
In the report, Philip M. Davis from Cornell University says that open access open access leads to increases in downloads, but not to increases in citations (their use), a key factor used in scientific publishing to assess a research article's relative importance and value. He believes the study will help scientists make informed decisions about where they publish their work and assist governments, granting institutions and universities with evaluating whether or not their open access policies are leading to greater dissemination of useful scientific knowledge.
"The widely-accepted 'open access citation advantage' appears to be spurious," said Davis. "There are many benefits to the free access of scientific information, but a citation advantage doesn't appear to be one of them."
To reach his conclusions, Davis ran several parallel randomized controlled trials. Upon publication, articles, including those from The FASEB Journal, were randomly assigned to either the open access or the subscription-access group. He then observed how these articles performed in terms of downloads and citations over three years.
He found that free access did not affect the number of citations a paper received, rejecting a widely-held belief that open access articles are cited more frequently because of their free-access status. The results are consistent over time across 36 journals covering the sciences, social sciences and humanities.
"A study like this is long overdue," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. "For years, institutions and organizations have promoted 'open access' policies under the assumption that some scientists cannot gain access to research reports because they or their institutions have to pay for subscriptions. Now we learn that 'open access' articles may be seen by more, but not cited (used) by more fellow scientists. It's probably time to drop the 'open access advantage' assumption and policies that follow from it."
Suppose many studies report that cancer incidence is correlated with smoking and you want to demonstrate in a methodologically sounder way that this correlation is not causal but just an artifact of the fact that the people who self-select to smoke are more prone to cancer. So you test a small sample of people randomly assigned to smoke or not, and you find no difference in their cancer rates. How can you know your sample was big enough to detect the reported correlation at all unless you test whether it's big enough to show that cancer incidence is significantly higher for self-selected smoking than for randomized smoking?
Many studies have reported a statistically significant increase in citations for articles whose authors make them OA by self-archiving them. To show that this citation advantage is not causal but just a self-selection artifact (because authors selectively self-archive their better, more citeable papers), you first have to replicate the advantage for the self-archived OA articles in your sample, and then show that the advantage is absent for the articles made OA at random. But Davis showed only that the citation advantage was absent altogether in his sample. The likely reason is that the sample was much too small (36 journals, 712 articles randomly OA, 65 self-archived OA, 2533 non-OA).
In a recent study (Gargouri et al 2010) we controlled for self-selection with mandated (obligatory) OA rather than random OA. The far larger sample (1984 journals, 3055 articles mandatorily OA, 3664 self-archived OA, 20,982 non-OA) revealed a statistically significant citation advantage of about the same size for both self-selected and mandated OA.
If and when Davis's requisite self-selected self-archiving control is ever tested, the outcome will either be (1) the usual significant OA citation advantage in the self-archiving control condition that most other published studies have reported -- in which case the absence of the citation advantage in Davis's randomized condition would indeed be evidence that the citation advantage had been a self-selection artifact that was then successfully eliminated by the randomization -- or (more likely, I should think) (2) there will be no significant citation advantage in the self-archiving control condition either, in which case the Davis study will prove to have been just a non-replication of the usual significant OA citation advantage (perhaps because of Davis's small sample size, the fields, or the fact that most of the non-OA articles become OA on the journal's website after a year).
Until that requisite self-selected self-archiving control is done, this is just the sound of one hand clapping.
Readers can be trusted to draw their own conclusions as to whether this study, tirelessly touted as the only methodologically sound one to date, is that -- or an exercise in advocacy.
Gargouri, Y., Hajjem, C., Lariviere, V., Gingras, Y., Brody, T., Carr, L. and Harnad, S. (2010) Self-Selected or Mandated, Open Access Increases Citation Impact for Higher Quality Research PLOS ONE 5 (10)