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6. Measure Impact: Journal impact metrics

Impact Factor - What is it?

Traditionally researchers are encouraged to publish in journals with higher impact factors in order to raise their research profiles. 

The mostly widely quoted measure for journals in JCR is the impact factor (JIF or IF)  found in the Journal Citation Reports (JCR). (Note: UC no longer subscribes to JCR).

The impact factor (IF) measures how often an article is cited in any year 

Most journals are rated as an impact of between 1 and 2

Many publishers will also provide information about impact of their journals on the journal web pages

Impact factors measure the impact of the journal not of individual articles 

The most highly rated journals are the weekly interdisciplinary journals Nature and Science 



Measuring the impact of a journal : journal impact factors

CiteScore  Elsevier's answer to Journal Impact Factors.  CiteScore ranking uses a three-year window to calculate the score. CiteScore counts the citations received in 2016 to documents published in 2013, 2014 or 2015, and divides this by the number of documents published in 2013, 2014 and 2015.

SJR (SCImago Journal Rank) - measures the scientific prestige of a scholarly source by assigning a relative score based on a citation network

SNIP (Source Normalized Impact per Paper) - measures contextual citation impact by weighting citations based on the total number of citations in a subject field. SNIP was developed using Elsevier (Scopus) citation data.

Adjusts citation impact measure  by taking into account the how often articles are cited in a particular field, calculates how quickly the paper is likely to have an impact, how well the database covers the topic,

SNIP offers the ability to benchmark and compare journals from different subject areas. This is especially helpful to researchers publishing in multidisciplinary fields.

Google Scholar

Scholar Metrics covers articles published between 2012 and 2016 based on citations in Google Scholar from 2017. Provides a quick method for gauging the visibility and influence of recent articles in scholarly publications. Contains a browsable list of the top 100 journals indexed in Google Scholar, with titles ordered by their five-year h-index and h-median metrics. Lists of top 20 journal titles are also available for both broad and specific subject areas.

Who to Contact


Phone: +6433693881
Internal Phone: 93881

More ways to assess a journal's impact

Although some journals are not covered by the major tools, this may not mean that they are not quality journals

You can also assess a journal's impact by answering the following questions:

  • Is the journal associated with a major research institution or professional body?
  • Are editorial board members significant figures within the research community?
  • Are the standards for manuscript acceptance high?
  • Is the refereeing system robust?
  • Are articles in the journal cited frequently and/or by well-regarded journals?
  • Is the journal covered by major article databases in the field?


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.

Calculation of 2010 IF of a journal:

A = the number of times articles published in 2008 and 2009 were cited by indexed journals during 2010.
B = the total number of "citable items" published in 2008 and 2009.
A/B = 2010 impact factor