There are many citation based indicators available for evaluating journals. The most common of them will be presented in this chapter.
Other assessment tools are also available, such as the JUFO classification. Read more about journal assessment from the chapter Journals.
Article and citation based indicators examine the average numbers of citations received within a certain period of time by publications (e.g. articles) published in the publication channel (e.g. a journal) over a certain period of time.
Indicator | Database | Method description | Time window |
---|---|---|---|
Journal Impact factor | Journal Citation Reports Web of Science Core Collection | Read more information in calculating the Journal impact factor. For example: IF 2020 = number of citations in 2020 to articles published in the journal in 2018–2019 divided by the number of articles published in the journal in 2018–2019.
| Citations from one year Publications from two years |
5 Year Impact Factor | Journal Citation Reports Web of Science Core Collection | Read more information on calculating the 5-Year Impact Factor. For example: 5-year IF 2020 = number of citations in 2020 to publications published in the journal in 2015–2019 divided by the total number of articles published in the journal in 2015–2019. | Citations from one year Publications from five years |
Journal Immediacy Index | Journal Citation Reports Web of Science Core Collection | Read more information on calculation methods of Journal Immediacy Index. For example: JII 2020 = number of citations in 2020 to publications published in the journal in 2020. | Citations from one year |
CiteScore | Scopus | Read more information about the CiteScore indicator. For example: CiteScore 2015 = number of citations in 2015 divided by the number of articles published in the journal in 2012–2014. | Citations from one year Publications from three years |
Algorithms are utilised for calculating Scimago and Eigenfactor indicators.
Indicator | Database | Method description | Time window | Notes |
---|---|---|---|---|
Scimago / SJR | Scopus |
| 3 years |
|
Eigenfactor Score | Web of Science |
| Citations from five years Publications from one year |
|
Field-normalised indicators refer to indicators that take into account differences and special characteristics of fields of science. The methods of categorising the fields of science widely and there is no single standardised method for doing it. The use of field-normalised indicators aims to allow for comparisons of publications accross disciplines. There is more information available on field-normalising in the chapter Methodological points of view.
Indicator | Database | Method description | Time window | Notes |
---|---|---|---|---|
Source normalized impact per paper, SNIP | Scopus |
| Citations from three years, publications from one year |
|
JCI (Journal Citation Indicator) | Web of Science |
| Publications from the three previous years and citations from the year being calculated as well as the three previous years. |