Research Impact Guide: Journal Impact Factor

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Journal Impact Factor is a measure of the frequency with which the "average article" in a journal has been cited in a given period of time.

Different sources will give different measures of journal impact as each is drawing from its own database content. CPUT provides access to two sources for journal impact figures: Scopus and Google Metrics. On the right, you will see examples of both.

When doing journal comparisons, be sure to compare like with like. Do not compare the SJR of Journal A with the h5-index of Journal B. Rather compare the SJR of both journals, or the h5-index.

Do not make cross-discipline comparisons as citation and publication behaviour differs in different fields.

The Scopus Journal Analyzer provides a measure of journal performance. Scopus includes over 21 000 peer-reviewed publications from 5,000 publishers; the Analyzer enables you to compare up to 10 journals simultaneously, back to 1996.

The Scopus Journal Analyzer includes 2 journal metrics:

1. SJR (SCImago Journal Rank) is a prestige measure based on the idea that all citations are not created equal. With SJR, the subject field, quality and reputation have a direct effect on the value of a citation. (About SJR)
    
2. SNIP (Source Normalized Impact per Paper) measures citation impact by weighting citations based on the total number of citations in a specific subject field. The impact of a single citation is given higher value in subject areas where citations are less likely, and vice versa. (About SNIP)

To use Journal Analyzer:

• Login to Scopus, then select Analyze Journal from the bar at the top. Search usings journal title, ISSN or publisher. Limits can be applied by Scopus Subject Categories. Here is the visual Scopus Journal Analyser Tutorial

Google Metrics bases its calculations on Google Scholar, which has a wide base that is not subject to quality control.

It gives two measures of journal impact: 

1. h5-index is the h-index for articles published in the last 5 complete years. It is the largest number h such that h articles published in 2009-2013 have at least h citations each.
   
   
2. h5-median for a publication is the median number of citations for the articles that make up its h5-index.

To access Google Metrics, follow these steps:

1. Go to Google Scholar.
   
   
2. Click Metrics near the top. 
   
   
3. Search for your journal title to vew the Google Metrics.