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Understanding Peer Review

U of T Licensed Citation Impact Tools

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Citation Impact Tools on the Public Web

Blog feed: Citation Impact Center

A Thomson Reuters sponsored community forum.

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This feed shows articles which have been tagged "oa.impact" by users of Connotea.

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Learn More About Citation Impact

Citation Impact and Open Access

What is the effect of Open Access on citations to articles?

  • A number of studies have now proved that there is a measurable increase in citation impact for open access articles.  The size of the increase varies and depends on the year and on the discipline (Swan & Chan, 2009).

This chronological bibliography focuses on the relationship between open access and impact.

What is Citation Impact?

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Citation analysis

  • Citation analysis can be used to determine the citation impact of authors, articles, and journals.  Beyond basic citation counts, there are measures such as the h-index and the g-index which are used to quantify the impact of an individual author.

Journal impact factor

Qualitative measures

  • Qualitative measures are output measures that are not easily quantifyable numerically. These may include stakeholder interviews, resource surveys, user feedback, focus groups, and questionnnaires,  that will capture information about the cycle of usage and impact.

Use/download data

  • Another method of assessing citation impact is to employ usage data such as the number of downloads for an article.  Researchers are now looking at whether download statistics could be used to predict future citations (SLU).

Scientometrics 2.0

  • There is a growing movement calling for the measurement of scholarly impact drawn from Web 2.0 data.  Given that researcher participation in Web 2.0 tools is not insignificant, and is likely to grow as the "born-digital" generation move toward and into tenured positions, social Web metrics may become increasingly influential (Priem and Hemminger, 2010).

Using Impact Factors

David Pendlebury of Thomson Reuters discusses why impact factors were originally introduced and how they really should be used.


Scopus Journal Analyzer provides access to 5 types of evaluation:

  1. SJR: SCImago Journal Rank  (more info)
  2. SNIP: Source Normalised Impact Per Paper  (more info)
  3. Citations: total number of citations received by a journal per year
  4. Documents: number of articles published by a journal per year
  5. % Not Cited: percentage of articles that were not cited in a journal per year

To access:

1. Go to Scopus

2. Click on Analytics

Analytics link on Scopus search page 
Fig. 1: Analytics link from Scopus search page



  • measures the prestige of scholarly sources i.e. a citation from a source with a high SJR has more weight than a citation from a source with a lower SJR
  • normalizes for differences in citation behaviour between subject fields
  • research behind SJR

SJR values of three journals

Fig. 2: Comparing the SJR values of JAMA, New England Journal of Medicine and the BMJ



  • measures contextual citation impact by weighting citations based on the total number of citations in a subject field
  • citation frequency of different fields taken into account
  • considers immediacy: how quickly a paper is likely to have an impact
  • research behind SNIP

SNIP values of three journals
Fig. 3: Comparing the SNIP values of JAMA, New England Journal of Medicine and the BMJ


Video 1. How SNIP and SJR are calculated.