The number of times a known article has been cited by other scholarly publications.
A citation count is a measure of impact rather than quality: an article may be cited in order to refute its conclusions, or as an example of poor practice.
For more discussion of the limitations and best uses of article citation counts, see the Library's Information for Researchers.
The usage count is an indicator of the level of interest in an article. It can provide useful information about newer articles which haven't yet been cited. But be aware that the data is platform-specific: when an article is available on multiple platforms, no single measure of usage can be treated as definitive.
Finding usage counts:
Regardless of where you find the data, always check to see how the count was determined (usually found on a help page) as each database and website counts usage differently. For example, the usage count on Web of Science reflects the number of clicks on a link to the full text of the article, plus the number of times the article is saved for use in a bibliographic management tool such as EndNote or Paperpile.
Whilst all sources of citation data are continually trying to extend their coverage, no single database indexes all the world's scholarly publications. Coverage of the arts and humanities may be less comprehensive, especially for books.
Generally, Web of Science and Scopus offer good coverage of sciences and social sciences, with less emphasis on humanities. Google Scholar covers all disciplines equally well, and captures 'grey literature' such as policy papers and technical reports in addition to journals. But the criteria for inclusion in Google Scholar are not wholly transparent.
Increasingly, e-journal platforms and subject-specialist bibliographic databases incorporate citation information acquired from these sources - you will see 'Cited By', 'Times Cited' or similar terms in their article records.
To find an article citation score on Web of Science, carry out a Basic Search for the article you are interested in. The number of times the article has been cited will be visible on the results page.
Click on the article title to view the full record and to see the full details of citing publications.
To be 100% confident that the citation score is correct, Web of Science enables you to run a Cited Reference Search, which will also find citations where the bibliographic details are incomplete or incorrect.
Create citation alerts and receive notification by email whenever your article is cited in the future. A very easy way to keep up-to-date.
To find out how many times a known article has been cited, search for the article by keyword and/or author. When you reach the document details for the required article, metrics are presented in the right-hand panel.
To create a citation alert:
Under the Cited by reference list, look for:
Many Google Scholar records include a Cited by score, which also acts as a link to the citing documents.
Search Web of Science, Scopus or Google Scholar for keywords relating to your subject. From your search results page:
It's not possible to sort Google Scholar search results by times cited. However, the Relevance ranking appears to take account of citations, so highly cited articles are likely to appear near the top of your results list.
In different scholarly disciplines, you will find differences in the typical number of authors on a paper, the breadth of the audience and the frequency of citation.
If you wish to analyse the impact of articles from different fields, you should use "normalised" or "field-weighted" citation metrics, to ensure that you are comparing like-with-like.
Scopus has developed a Field-Weighted Citation Impact score for articles, and this score can be benchmarked against the best in the field:
Further reading: How are article metrics used in Scopus?
Limitations: Most field-weighted indicators rely upon a subject classification assigned by the database compilers, which inevitably has a subjective element. See Wang & Waltman (2015): Large-scale analysis of the accuracy of the journal classification systems of Web of Science and Scopus.