CiteScore (CS) of an

academic journal An academic journal (or scholarly journal or scientific journal) is a periodical publication in which Scholarly method, scholarship relating to a particular academic discipline is published. They serve as permanent and transparent forums for the ...

is a measure reflecting the yearly average number of

citation A citation is a reference to a source. More precisely, a citation is an abbreviated alphanumeric expression embedded in the body of an intellectual work that denotes an entry in the bibliographic references section of the work for the purpose o ...

s to recent articles published in that journal. It is produced by

Elsevier Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ...

, based on the citations recorded in the

Scopus Scopus is a scientific abstract and citation database, launched by the academic publisher Elsevier as a competitor to older Web of Science in 2004. The ensuing competition between the two databases has been characterized as "intense" and is c ...

database. Absolute

ranking A ranking is a relationship between a set of items, often recorded in a list, such that, for any two items, the first is either "ranked higher than", "ranked lower than", or "ranked equal to" the second. In mathematics, this is known as a weak ...

s and

percentile rank In statistics, the percentile rank (PR) of a given score is the percentage of scores in its frequency distribution that are less than that score. Formulation Its mathematical formula is : PR = \frac \times 100, where ''CF''—the cumulative fr ...

s are also reported for each journal in a given subject area. This journal evaluation metric was launched in December 2016 as an alternative to the

Journal Citation Reports ''Journal Citation Reports'' (''JCR'') is an annual publication by Clarivate. It has been integrated with the Web of Science and is accessed from the Web of Science Core Collection. It provides information about academic journals in the natur ...

(JCR)

impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ...

(IF), calculated by

Clarivate Clarivate Plc is a British-American Public company, publicly traded analytics company that operates a collection of subscription business model, subscription-based services, in the areas of bibliometrics and scientometrics; business intelligenc ...

. CiteScore is based on the citations collected for articles published in the preceding four years, instead of two or five in the JCR IF. This enhanced methodology was introduced with the release of CiteScore 2019 in June 2020. At launch, CiteScore's neutrality was questioned by bibliometrics experts like Carl Bergstrom, who found it appeared to favour Elsevier's titles over Nature's.

Calculation

In any given year, the CiteScore of a journal is the number of citations, received in that year and in previous three years, for documents published in the journal during the total period (four years), divided by the total number of published documents (articles, reviews, conference papers, book chapters, and data papers) in the journal during the same four-year period:

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For example, ''Nature'' had a CiteScore 2021 of 70.2:

\text_ =  =  = 70.2

For example, the 2017 CiteScores were reported first in 2018 when all data was available completely. CiteScores are typically released in late May, approximately one month earlier than the JCR impact factors. Scopus also provides the projected CiteScores for the next year, which are updated every month.

Pre-2020 formula

Before 2020, the score was calculated differently: in a given year, the CiteScore of a journal was the number of citations received in that year of articles published in that journal during the three preceding years, divided by the total number of "citable items" published in that journal during the three preceding years:

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For example, ''Nature'' had a CiteScore of 14.456 in 2017:

\text_ =  =  = 14.59

Because the calculation method changed, knowing the calculation date is an important detail when comparing CiteScores. For example, the ''Nature'' CiteScore for 2017 calculated with the post-2020 method is 53.7.

Comparison to JCR Impact Factor

CiteScore was designed to compete with the two-year JCR impact factor, which is currently the most widely used journal metric. Their main differences are as follows: Another difference is the definition of the "number of publications" or "citable items".

References

{{DEFAULTSORT:CiteScore Journal ranking