Unrestricted Access


Eigenfactor.org is a database of both Eigenfactor scores and article influence scores calculated by eigenfactor.org and made freely available.  The Eigenfactor score is intended to measure the importance of a journal in the scientific community  by considering the origin of the incoming citations and is thought to reflect how frequently an average researcher would access content from that journal.  The Eigenfactor score is influenced by the size of the journal – the score doubles in size when the journal doubles in size, in terms of the number of articles published per year.  The Article Influence score measures the average influence of articles in the journal and is therefore comparable to the ISI Impact Factor.


A FAQ and About page are available, as well as other informative pages from the main naivigation bar.

User tools and features

The Eigenfactor approach is thought to be more robust than the impact factor metric.  The latter purely counts incoming citations without considering the significance of those citations.  The Eigenfactor score is correlated with total citation count for medical journals, these metrics provide significantly different information.,  For a given number of journals, those from more important journals will receive a higher Eigenfactor score.  Users may perform three separate types of searches:  by journal title, by ISI Category (broad medical subjects), and by year of publication.  Information is typed into the appropriate search text box.

Dates covered

2000 – 2011.

Updating frequency

Citations are processed for calendar year periods and are added when processing is complete so there is not a set updating schedule.


Published medical journals.

Type of coverage

Rates/ranks significance or impact of published medical journal articles.

Print counterpart or
related resources

ISI’s Journal Citation Index is a near resource but they are independently produced and use different metrics for ranking articles/journals.

Producer/content provider

Developed by Jevin West and Carl Bergstrom of the University of Washington

Vendor/electronic presentation provider

Department of Biology, University of Washington