Rockville MD — While the number of times a scientific article is cited by other articles is currently the gold standard for ranking its impact, online publishing offers another measure: the number of unique downloads.

A recent analysis in the online Journal of Vision finds that downloads are a good predictor of citations — and they are available significantly faster.

The analysis was published in an editorial by Journal of Vision (JOV) Editor-in-Chief Andrew Watson. (http://journalofvision.org/9/4/i/) JOV recently began publishing download counts for every published article. The journal also ranks the top 20 articles by download.

How do unique downloads compare with the more traditional citations counts? Very well, it turns out. Watson reports an overall correlation of 0.74 between downloads and citations for individual articles in JOV.

But who needs this new metric, if the old one worked well? Anyone in a hurry. Download counts mirror citations, but are available about two years earlier.