Impact Factor of Elsevier Journals
Elsevier is one of the world most prominent scientific publishers. One of its major products is Scopus. Scopus is a monthly updated source of citation information for more than 25,000 titles. It covers editions from all over the world, published by various publishers, and in any subject area. Such a vast amount of data should be analyzed and evaluated in a proper way in order to be of use for researcher, funders and other science-related organizations.
When evaluating the importance and impact of a journal, we usually turn to various metrics such as Journal Impact Factor or CiteScore. Both measures may seem similar, yet they have certain differences.
In this article, we will discuss the impact factor of Scopus indexed journals. We will elaborate on Journal Impact Factor and CiteScore metrics, cover the recent changes that the CiteScore underwent this year, and compare both measures.
Important: the term Journal Impact Factor itself is used exclusively for Web of Science. All other simply use their formula. They are not officially called impact factors.
CiteScore and Journal Impact Factor for Journal Assessment
There exist many citation databases that apply a slightly modified impact-factor formula to evaluate the indexed journals. Basically, all of them may be called an impact-factor, despite having different official names. For example, it is SJR and CiteScore for Scopus-indexed journals. The two metrics are used to assess a journal's importance according to the number of citations.
Currently, CiteScore is getting more essential when selecting the journal. It implies a more comprehensive calculation and equals the number of citations a journal received within one year to the number of published documents in three previous years divided by the number of documents indexed in Scopus that published within the same three-year period.
While Journal Impact Factor is the average sum of the citations received within a year to publications of two previous years, divided by the number of citable documents in the same two-year period.
As CiteScore is practically based on the idea of the Journal Impact Factor, it would be suitable to present the main differences between CiteScore and Journal Impact Factor, which are:
- CiteScore calculations are based on a four-year timeframe, while the Journal Impact Factor is measured on a two-year one.
- CiteScore involves a wide range of documents, while the Journal Impact Factor focuses only on articles and reviews.
How Do CiteScore and Impact Factor Correlate?
Recently, Elsevier changed the way CiteScore is calculated. The changes include the types of assessed documents and extended a citation window up to four years, which used to be limited to a one-year timeframe only.
Some journals are indexed both in Scopus and Web of Science, which may make them have a Journal Impact Factor (JIF) as well and appear on Journal Citation Reports (JCR).
In order to assess the correlation between CiteScore metrics and Impact Factor, there was conducted research. The findings suggest that the changed methodology generally leads to an increased CiteScore for the majority of journals and potential reshuffling of individual journal ranks that have pretty close CiteScores. As for the correlation with Journal Impact Factor, the new CiteScore calculations seem to be less prone to variation than Impact Factor. However, it was noticed that the results vary depending on the subject area due to the differences in the number of citations and editorial material.
Another so-called “Scopus Impact Factor” is SJR, which may be found on Scimago Journal & Country Rank website. It is a kind of report that is in some way similar to JCR, but one should have in mind that Scopus JCR does not exist. So if you are looking for that report, it is better check Scimago website, which the second reliable source of information on Scopus metrics after Scopus official website.