Peter Suber at Open Access News pointed me to a very interesting pre-print article about the citation impact of open access journal articles. Citation Impact of Open Access Articles vs. Articles available only through subscription (“Toll-Access”) is still in the analysis stages, but they seem to have found that with physics and mathematics journals, those that offer open access have a greater citation impact.

According to Suber:

Brody and the six other members of his project are extending their study beyond physics and mathematics. They are not only collecting and analyzing data from a large number of other fields. They are organizing the data behind an interactive interface allowing users to select any combination of research specializations and display graphs of their data on the same page. For example, here’s the page on geriatrics, acoustics, and linguistics.

Nice to see empirical research supporting the idea that open access journal articles will have greater scholarly impact.