Although this guide provides a basic introduction to JCR and Impact Factors, you will also want to consult our guide just on that subject:
What is a Journal's Impact Factor, and How Can I Find It?
An Impact Factor (IF) provides a quantitative assessment of a journal's influence or impact. Thomson Scientific (now Thomson Reuters Scientific) offers the Impact Factor via Journal Citation Reports (JCR). According to Thomson Reuters, the Journal Impact Factor is the frequency with which the “average article” in a journal has been cited in a particular year. A journal’s Impact Factor is determined by dividing the number of citations in the JCR year by the total number of articles published in the two previous years. A Journal Impact Factor of 4.0 means that, on average, the articles published in that journal within the past three years have been cited four times. There must be at least two years of data in order to calculate the Impact Factor.
Using Impact Factors Wisely:
As Thomson Reuters indicates on their "Information About" page, one should not depend entirely on JCR data to evaluate a journal because:
Some Additional Methods for Constructing Impact Factors:
Google Scholar - From the Advanced Search screen, enter author and title information to obtain cited references. Publish or Perish may be used to track an author's impact using Google Scholar.
eigenfactor.org - Ranking and Mapping Scientific Journals - Note that this site says that "Thomson Reuters (Scientific) Inc. provided the data used in calculating the Eigenfactor™ Score, the Article Influence™ Score, and other analyses." In other words, there is a link between this product and JCR.
Journal-Ranking.com by RedJasper - Corporate website. Claims that it is "perhaps the first online journal ranking system in the world which allows any individual to conduct citation analyses among more than 7000 academic journals with regards to his/her own interests." Although you can click the ranking tab and search for a journal, "if you are not a registered user, you would NOT be able to change any settings below except for the last one Journals to be ranked. Create an account if you wish to get fuller functionality.
Individual publishers track Impact Factors for their journals. For example, here is a recent alert from Elsevier on their Business and Management Journals.
And homepages for individual journals often discuss Impact Factor for that publication. As an example on the homepage for Wiley's Journal of Social Issues, you would see the Impact Factor front and center, as illustrated below.
More on Journal Citation Reports (JCR):
Normally, to find JCR, you would go to the Mildred F. Sawyer's home page, and select "Databases by Subject." Choose "Business and Management" or "Social Sciences" and click on Journal Citation Reports near the bottom of the list. However, here is a direct link.
To Utilyze JCR:
Additional Information about JCR and the Thomson (ISI) Impact Factors can be found at:
JCR Quick Reference Guide (21p) PDF:
Thomson Reuters Online Tutorial for JCR:
Resources that Might Help Explain Impact Factors Further .....
Additional Non-Thomson Materials Discussing Impact Factors:
Elsevier on Journal and Article Metrics.
Springer on Impact Factors
The below-linked two-page overview was created by our Thomson sales rep. It does a good job of providing an introduction to what JCR is and does. Following that is a PDF created by Thomson to introduce the product to users.