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Measuring Impact

How are citations counted?

Citation count is the most basic article-level bibliometric, and the measure used in all other bibliometrics. Each time an article is used as a reference in another article, that counts as a citation. An article can be used as a reference for many reasons, not all of them positive. That's why citation counts are used to measure the impact of an article, not its quality.

Scholarly Impact can help create reports and visualizations comparing publications using citation counts and other article-level bibliometrics. Please contact us for assistance.

Five databases/search engines provide citation counts:

Each of these databases/search engines only count citations in research outputs included in their index. The result of this is that citation counts for the same research output can be different in the five sources.

For example: “Prostate cancer vaccines” (DOI: 10.4161/onci.24523) has been cited 27 times in Scopus, 28 times in Web of Science, 33 times in Dimensions, 38 times in Lens, and 47 times in Google Scholar. (Citation counts as of 8/28/2024.)

Consequently, it is important to use the same source when using citation counts to measure the impact of research outputs.

Weighted Article-Level Metrics

Field-Weighted Citation Impact (FWCI) is an article-level bibliometric available from Scopus.

It shows how well cited a document is when compared to similar documents. A value greater than 1.00 means the document is more cited than expected according to the average. It takes into account:

  • The year of publication
  • Document type, and
  • Disciplines associated with its source.

The FWCI is the ratio of the document's citations to the average number of citations received by all similar documents over a three-year window. Each discipline makes an equal contribution to the metric, which eliminates differences in researcher citation behavior.

NOTE: FWCI is available in Scopus but cannot be exported. Please contact Scholarly Impact for assistance with FWCI.

Field Citation Ration (FCR) is an article-level bibliometric available from Dimensions.

The FCR indicates the relative citation performance of a publication when compared to similarly-aged articles in its subject area. A value of more than 1.0-1.5 indicates higher than average citation, when defined by FoR subject code, and publication year. The FCR is calculated for all publications in Dimensions which are at least 2 years old and were published in 2000 or later.

Relative Citation Ratio (RCR) is an article-level bibliometric available from PubMed.

The RCR indicates the relative citation performance of a publication when comparing its citation rate to that of other publications in its area of research. A value of more than 1.0 shows a citation rate above average. The article’s area of research is defined by the articles that have been cited alongside it. The RCR is calculated for all PubMed publications which are at least 2 years old.