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Impact Factor and Other Ways of Assessing the Research Value of a Journal: Journal Impact Factors

Various ways to assess the research value of a journal.

What is this measure?

The impact factor, often abbreviated IF, is a measure reflecting the average number of citations to articles published in science and social science journals.  

The impact factor of a journal for a given year is the average number of citations received per paper published in that journal during the two preceding years. If a journal has an impact factor of 3 in 2008, then its papers published in 2006 and 2007 received 3 citations each on average.

The 2008 impact factor of a journal would be calculated as follows:

A = the number of times articles published in 2006 and 2007 were cited by indexed journals during 2008

B = the total number of "citable items" published by that journal in 2006 and 2007.

2008 impact factor = A divided by B

The 2008 impact factors are actually published in 2009--they cannot be calculated until all of the 2008 publications have been received and processed by the indexing company.

It is frequently used as a proxy for the relative importance of a journal within its field, with journals with higher impact factors deemed to be more important than those with lower ones.

Due to differences in publishing patterns by discipline, impact factors cannot be compared between disciplines.

Finding a journal impact factor

Find the Library's link to:

1. Once connected, select your edition and year
2. Select Search for a specific journal, then click Submit.
 
 
            

3. The Journal Search page will let you search for journals by full journal title, abbreviated journal title, title word, or ISSN. Or click view list of full journal titles to see a complete list of titles.

  
 
 
     
 
 
 4.  The results page will show the impact factor for your selected journal. For additional analysis and explanation of impact factor and other measures,
click the  journal's title  (e.g. NATURE). 
 
     
 
   
 
 
 
 
 
 
 
 
5. For additional analysis and explanation of impact factor and other measures, click the journal's title. Each journal title is assigned to one or more “Subject Categories.” These categories can be found under the  Journal Information  heading (immediately below the ranking chart).
 
In this example, NATURE belongs to a single subject category: MULTIDISCIPLINARY SCIENCES      
    
 
 
 
 
 
 
 6. Click the  Journal Ranking button to see the rank of the journal in each category.
 In this example, NATURE has the highest Impact Factor out of the 50 journals in the “Multidisciplinary sciences” category.
 
 
 
 
          
 
 
 
 

To find impact factors for journals in a discipline

To view the Impact Factor for a group of journals by Subject Category:

 

  • Begin a new search by clicking the Welcome button in the upper left of the main JCR screen.
  • Select View a group of journals by Subject Category , then click Submit.
  • The Subject Category Selection page will let you search by one or more subject categories. Select a subject category (e.g. Physiology), check View Journal Data , select sort by: Impact Factor , then click Submit .

     

The results page will show the impact factor of the journals in your selected category or categories. For additional analysis and explanation of impact factor and other measures, click the  journal's title  (e.g. ACTA PHYSIOL).