CiteScore (CS) of an
academic journal
An academic journal or scholarly journal is a periodical publication in which scholarship relating to a particular academic discipline is published. Academic journals serve as permanent and transparent forums for the presentation, scrutiny, and d ...
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 of ...
s to recent articles published in that journal. This journal evaluation metric was launched in December 2016 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'', the ScienceDirect collection of electronic journals, '' Trends'', th ...
as an alternative to the generally used
JCR impact factor
The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ...
s (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 intelligence, ...
). CiteScore is based on the citations recorded in the
Scopus
Scopus is Elsevier's abstract and citation database launched in 2004. Scopus covers nearly 36,377 titles (22,794 active titles and 13,583 inactive titles) from approximately 11,678 publishers, of which 34,346 are peer-reviewed journals in top-l ...
database rather than in JCR, and those citations are collected for articles published in the preceding four years instead of two or five.
Calculation
In any given year, the CiteScore of a journal is the number of citations, received in that year and previous 3 years, for documents published in the journal during that 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:
[
For example, ''Nature'' had a CiteScore 2019 of 51.0
Note that 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.][ Note also the calculation date for each given CiteScore as later additions, corrections or deletions to the data will not lead to a score update. Scopus also provides the projected CiteScores for the next year, which are updated every month.][
]
Old calculation
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:[
For example, ''Nature'' had a CiteScore of 14.456 in 2017:
Because the calculation method changed, knowing the calculation date is an important detail when comparing CiteScores. For example, the ''Nature'' CiteScore in 2017, but calculated with the method of 2020, is 53.7.CiteScore 2017]
243783/4539=53.7
CiteScore vs. Journal 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