Understanding the Journal Impact Factor and Journal Citation Index

1. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous)
09-05-2022 1
Journal Impact Factor (JIF)
Vs
Journal Citation Index (JCI)
Associate Professor,
Chalapathi Institute of Pharmaceutical Sciences
(Autonomous)
Koushik Yetukuri

2. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 2
The Web of Science™ is the world’s most trusted publisher-
independent global citation database. Guided by the legacy of
Dr Eugene Garfield, inventor of the world’s first citation index,
the Web of Science is the most powerful research engine,
delivering your library with best-in-class publication and citation
data for confident discovery, access and assessment.
(1925 – 2017)

3. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 3
• A citation index is built on the fact that citations in science serve as
linkages between similar research items, and lead to matching or
related scientific literature, such as journal articles, conference
proceedings, abstracts, etc.
• For example, a paper's influence can be determined by linking to all the
papers that have cited it. In this way, current trends, patterns, and
emerging fields of research can be assessed. Eugene Garfield, the
"father of citation indexing of academic literature," who launched
the Science Citation Index, which in turn led to the Web of Science.

4. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 4

5. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 5

6. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 6

7. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 7

8. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 8
Journal Citation Reports™ (JCR) provides you with the transparent, publisher-neutral data and
statistics you need to make confident decisions in today’s evolving scholarly publishing
landscape, whether you’re submitting your first manuscript or managing a portfolio of
thousands of publications.

9. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 9
• Since the publication of the first Journal Citation Reports (JCR)™ in 1976, the Journal Impact Factor
(JIF)™ has become a standard way to measure the citation impact of a journal.
• The JCR was created to describe and define the network of journals as an aggregate of the article
citation network in the Science Citation Index™.
• It was intended to provide an objective measure regarding scholarly use of journals to support
both libraries and authors in publication evaluation.

10. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 10
• The utility of the JIF to these simple purposes
evolved to other areas of research assessment,
helping authors choose where to publish papers
and enabling publishers and editors to monitor the
success of their portfolios.
• Due to the rigorous and independent selectivity
process used, inclusion in the JCR has also become
a hallmark for editorial quality and research
integrity, helping the research community identify
trusted sources of scholarly content.

11. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 11

12. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 12

13. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 13

14. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 14

15. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 15

16. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 16
• The Journal Impact Factor (JIF) is a ratio which
divides a journal’s received citations by a count
of its published articles.
• It’s not a mathematical average, but it does
provide an approximation of the mean citation
rate for a typical article.

17. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 17
The anatomy of the Journal Impact Factor
Citations in 2020 to items published
In 2018 (4,624) + 2019 (4,346)
Number of citable items in
2018 (197) + 2019 (192)
8,970
389
= = 23.059
Journal Impact Factor Calculation

18. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 18
Citations in 2020 to items published
In 2018 (4,624) + 2019 (4,346)
Number of citable items in
2018 (197) + 2019 (192)
8,970
389
= = 23.059
JIF numerator
A subset of all citations to this journal in the calendar year: citations only to
items with a publication date from the prior two years. These citations are
sourced from all item types included in Web of Science Core Collection
indexes:

19. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 19
Citations in 2020 to items published
In 2018 (4,624) + 2019 (4,346)
Number of citable items in
2018 (197) + 2019 (192)
8,970
389
= = 23.059
JIF denominator:
• The number of citable items this journal published in the prior two years.
Items identified in Web of Science Core Collection as Articles or Reviews are
included here as citable items.
• These represent the size of the scholarly contributions of the journal. Items
like editorials, letters, and news items are excluded from the denominator.

20. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 20
Citations in 2020 to items published
In 2018 (4,624) + 2019 (4,346)
Number of citable items in
2018 (197) + 2019 (192)
8,970
389
= = 23.059
JIF number:
A typical article or review from this journal has been cited about 23 times, one
or two years after publication.

21. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 21
Why two years?
It takes time for articles to be cited, and these rates vary by field. Articles
typically begin to reach a citation peak after two years in many fields. Some
fields have a slower velocity and reach their peak over longer periods of
time. The Five-year Journal Impact Factor may be a better choice in those
categories.
• JIF is a journal-level metric.
• It does not measure the contribution of individual papers or authors.

22. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 22
• The Journal Citation Indicator is a new
way to measure the citation impact of a
journal’s recent publications using a field-
normalized calculation.
• This new approach provides a single
value that is easy to interpret and
compare, complementing current journal
metrics and further supporting
responsible use. Starting from the 2021
JCR release, it will be calculated for all
journals in the Web of Science Core
Collection.

23. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 23
Journal Citation Indicator:
The value represents the average category-normalized citation impact for papers published
in the prior three-year period.
For example,
the 2020 Journal Citation Indicator will be calculated for journals that published citable items
(i.e. research papers classified as articles or reviews in the Web of Science) in 2017, 2018
and 2019, counting all citations they received from any document indexed between 2017
and 2020

24. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 24

25. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 25
• The value of the Journal Citation Indicator is the mean
Category Normalized Citation Impact (CNCI) for all
articles and reviews published in the most recent three
years (e.g. between 2017 and 2019 for the 2020 indicator
value).
• CNCI (see here for full description) is an article-level
metric that uses three important facets for normalization,
namely field (category), document type (article, review,
etc.) and year of publication. CNCI represents the relative
citation impact of a particular paper as the ratio of
citations compared to a global baseline.

26. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 26
A CNCI of 1.0 represents world average – values higher than 1.0 correspond to more than average
citation impact (e.g. 2.0 being twice the average), and values lower than 1.0 define less than
average citation impact (e.g. 0.5 being half the average).

27. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 27
The Journal Citation Indicator is
designed to complement the JIF – the
original and longstanding metric for
journal evaluation – and other metrics
currently used in the research
community. In addition to the use of
normalization, there are several key
differences between the Journal
Citation Indicator and the JIF.

28. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 28
The JIF calculation is based on citations made in the
current year, while the Journal Citation Indicator counts
citations from any time period following publication, up
to the end of the current year.
• For example, the Journal Citation
Indicator’s calculation on three years
of publications contrasts with the
two-year window employed for the
JIF.
• This three-year calculation enables
the Journal Citation Indicator to be as
current as possible, while also
allowing more time for publications
to accrue citations.

29. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 29

30. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 30

31. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 31

32. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 32

33. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 33

34. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 34

35. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 35

36. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 36
https://clarivate.com/products/scientific-and-academic-research/research-discovery-and-workflow-
solutions/web-of-science/core-collection/editorial-selection-process/editorial-selection-process/
https://www.linkedin.com/pulse/whats-journal-quartile-rankings-research-dr-koshal-k-bagelu-/
https://clarivate.com/webofsciencegroup/solutions/web-of-science/

37. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 37

38. Chalapathi
Institute of Pharmaceutical Sciences
(Autonomous) Lam, Guntur, AP
09-05-2022 38