NOTE: This Blog Post Below Discusses an Article We Linked to On Wednesday. The Post Can Be Accessed Here.
The results [of a study by Phillip Davis] stand in contrast to those found by open access advocate Stevan Harnad, from Southampton University. He led a study that was published in PloS ONE last year but used a different method (based on comparing non self-archived and self-archived subscription journal articles) to find open access articles received “significantly more” citations.
Harnad criticised the current study as “the sound of one hand clapping” with “no basis” for drawing the conclusions it did. Davis’ sample is likely “too small” to show the citation advantage, he says, and the study does not look properly at the key question of the extent to which the citation advantage is real versus simply an artefact of researchers selectively archiving their better (and therefore more citable) papers.
Davis’ study notes that articles that were also self-archived did receive 11% more citations on average within the three years, but with only 65 articles (2%) the effect was statistically insignificant.
“We do leave open the possibility that there is a real citation effect as a result of self archiving but that we simply do not have the statistical power to detect it,” says Davis, though he also stresses that it would “difficult, if not impossible” to tease out the whether any effect was the result of enhanced access or just better (more citable) papers being self-archived.
Hat Tip and Thanks: Peter Suber and Stevan Harnad