Citation Analysis, measuring your research impact : Journal Impact Factor

Definition: The journal impact factor measures the importance of a journal by calculating the times it's articles are cited.

How Impact Factor is Calculated: The calculation is based on a two-year period and involves dividing the number of times articles were cited by the number of articles that are citable.

Be Aware

Experts stress that there are limitations in using impact factors to evaluate a scholar's work. There are many reasons cited for not relying on impact factor alone to evaluate the output of a particular individual. Among these are the following:

• A single factor is not sufficient for evaluating of an author's work.
• Journal values are meaningless unless compared within the same discipline. Impact factors vary among disciplines.
• The impact factor was originally devised to show the impact of a specific journal, not a specific scholar. The quality and impact of the author's work may extend beyond the impact of a particular journal.

According to Jim Testa, a researcher for ThomsonReuters Scientific, the most widespread misuse of the Impact Factor is to evaluate the work of an individual author (instead of a journal). "To say that because a researcher is publishing in a certain journal, he or she is more influential or deserves more credit is not necessarily true. There are many other variables to consider." (interview 6/26/2008 in Thomson Reuters blog entry)

Journal Impact Factors

Journal Impact Factor is from Journal Citation Report (JCR), a product of Thomson ISI (Institute for Scientific Information). JCR provides quantitative tools for evaluating journals. The impact factor is one of these; it is a measure of the frequency with which the "average article" in a journal has been cited in a given period of time.

Journal Citation Reports^® tutorial

Overview — Journal Citation Reports provides easy access to data that helps you evaluate and compare scholarly journals. It is an essential, comprehensive, and unique resource tool for journal evaluation, using citation data drawn from over 7,500 journals from over 3,300 publishers in over 60 nations.

Journal Citation Reports is the only source of citation data on journals. It includes virtually all specialties in the areas of science, technology, and the social sciences. Moreover, it shows the relationship between citing and cited journals in a clear, easy-to-use framework.

Journal Citation Reports can show:

• Most frequently cited journals in a field
• Hottest journals in a field
• Highest impact journals in a field
• Leading journals in a field
• Related journals in a field
• Citation characteristics for a subject category

To use Journal Citation Reports, follow the steps below:

1. Open Journal Citation Reports.
2. Select either the Science or Social Sciences Edition and the Year.
3. Select an option to search for a specific journal, or to view a group of journals.
4. To search for a specific journal, you may search by Full or Abbreviated journal title, title word, or ISSN.
5. Click on the journal title to see Journal Information, Impact Factor, Immediacy Index, Cited Half-Life, Cited Journal Graph,etc.

For more information about Journal Citation Reports, click on the Information for New Users located in the upper right hand corner of the database opening page, or view the Journal Citation Reports tutorial created by Thomson ISI.