This is the "Impact Factor" page of the "BIM 116: Writing Assignment #1" guide.
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BIM 116: Writing Assignment #1  

Last Updated: Sep 28, 2016 URL: Print Guide RSS UpdatesEmail Alerts

Impact Factor Print Page

Impact Factor

Impact Factor:

  • Is a number used to indicate how influential, or important a particular journal is.

  • Was developed in the late 1950’s by Eugene Garfield at the Institute of Scientific Information (ISI), now called Thompson Scientific (a large publisher). 

  • Impact Factor refers to a journal, not to an article, and not to an author  (although publishing an article in a journal with a high impact factor is generally considered prestigious) 

  • The benefits and pitfalls of impact factors are a widely discussed topic in academia.  Others measures exist to evaluate the influence of journals, articles, and authors.  

How To Find a Journal’s Impact Factor:

  1. From the Library Databases Page select  Journal Citation Reports (aka: JCR, and InCites Journal Citation Reports). 
    From  Library Home Page --> Databases A-Z --> Enter “Journal Citation Reports”

  2. To find Impact Factor for a journal:
    • Enter the name of the journal in the  GO TO JOURNAL PROFILE box
    • Impact factor is in the second column labeled “Journal Impact Factor.” 

    • Boxes on the left allow you to limit by: year, Select the year you want and either the Science or Social Sciences edition of JCR. 
    • Unless your assignment specifies otherwise, use the default options and choose the most recent year available
      (this is usually at least 1 year ago, i.e., in 2012 the most recent impact factors available will be for 2011)

How Impact Factors Are Calculated:

2005 Impact Factor for Journal X  =  A / B,  where:

A = Number of times articles published in Journal X in 2003-2004 were cited by indexed journals in 2005

B = Number of articles published in Journal X in 2003-2004

     Things to be aware of:

  • "indexed journals" means journals indexed by Thompson Scientific (makers of the Web of Science database).  If Thompson Scientific doesn't index the journal, it doesn't get included.

  • "number of articles" Thompson Scientific also decides what counts as an "article" (or "citable item").  Usually included are: articles, communications, reviews, notes, etc.  Excluded are "news" type items, letters to the editor, etc.

  • The lower the denominator, the higher the impact factor.

  • A journal's impact factor refers to a certain year: impact factors do vary from year to year, although most established journals tend to have fairly consistent impact factors (i.e., they don't vary widely). 

For more information, see:  Using JCR Wisely 


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