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Research Metrics

Journal Level Metrics

Journal Level Metrics

journal icon

 

Journal level metrics are used to indicate the impact of scholarly journals – not articles or authors. Researchers often use the metrics to identify significant journals in a field, and inform their publishing strategies to maximize the reach of their works.

The metrics are only available for the journals indexed in the specific citation databases. For example, only journals indexed by Web of Science Core Collection (SCIE, SSCI, AHCI, ESCI) will have journal impact factors.

Journal Impact Factor

Journal Impact Factor (JIF)

Journal Impact Factor (JIF) can essentially be defined as the annual average number of citations to papers in any given journal in the two preceding years:

Impact Factor Numerator - Cites to recent items:  The numerator looks at citations in a particular JCR year to a journal's previous two years of content. For example, the 2017 Journal Impact Factor for a journal would take into account 2017 items that cited that journal's 2015 or 2016 content. The numerator includes citations to anything published by the journal in that 2015-2016 timeframe.  Impact Factor Denominator - Number of recent items:  The denominator takes into account the number of citable items published in the journal in 2015 and 2016. Citable items include articles and reviews. Document types that aren't typically cited, e.g. letters or editorial materials, are not included in the Impact Factor denominator.

 

JIF is updated annually and varies every year.

It is only available for the journals indexed in Web of Science Core Collection, including:​

  • Science Citation Index Expanded (SCIE)​
  • Social Sciences Citation Index (SSCI)​
  • Arts & Humanities Citation Index (AHCI)​
  • Emerging Sources Citation Index (ESCI)​

Web of Science Core Collection is curated by an expert team of in-house editors​, which, as the publisher explains, includes only journals demonstrating high levels of editorial rigor and best practice.

 

Journal Impact Factor Quartile

The Journal Impact Factor quartile is the quotient of a journal’s rank in category (X) and the total number of journals in the category (Y), so that (X / Y) = Percentile Rank Z.

  • Q1     0.0 < Z ≤ 0.25
  • Q2     0.25 < Z ≤ 0.5
  • Q3     0.5 < Z ≤ 0.75
  • Q4     0.75 < Z

Note: Journals may appear in multiple Web of Science categories, and are at different quartiles among the categories.

 

Use and limitations

Use
  • It is well-known, easy to calculate and understand.
  • It can be useful in comparing the relative influence of journals within a discipline, as measured by citations.
limitations
  • It does not take into account of the large variation in citation levels across subjects.
  • It is a measure of "average citation performance" and gives no indication of the skewed distribution of citations.
  • It covers a short time span, which may not be useful for subjects with long half-life of citations and references in them.
  • There are concerns about data and manipulation, e.g., journals requesting submitting authors to reference excessive papers in the previous issues.

 

Access

Journal Citation Reports (JCR): http://find.lib.hku.hk/record=alma991019172539703414

 

  1. Enter the name or ISSN of the journal to perform a search. Select the journal title from the drop down list.

    Screen capture 1

     
  2. At the journal profile page, scroll down to the section “Journal’s performance” for Journal Impact Factor and Journal Impact Factor Quartile.

    Screen capture 2

 

References

  • Declaration on Research Assessment (DORA). (2024). Guidance on the responsible use of quantitative indicators in research assessment. DORA. https://doi.org/10.5281/zenodo.10979644
  • Indicators Glossary. https://incites.help.clarivate.com/Content/Indicators-Handbook/ih-glossary.htm?Highlight=impact%20factor
  • Journal Citation Reports: Learn the Basics. https://clarivate.libguides.com/jcr#s-lib-ctab-12181545-0
  • Journal Impact Factor. Metrics Toolkit. https://www.metrics-toolkit.org/metrics/journal_impact_factor/
  • Mingers, J., & Leydesdorff, L. (2015). A review of theory and practice in scientometrics. European Journal of Operational Research, 246(1), 1-19. https://doi.org/10.1016/j.ejor.2015.04.002

CiteScore

CiteScore

CiteScore is based on the number of citations to documents (articles, reviews, conference papers, book chapters, and data papers) by a journal over four years, divided by the number of the same document types indexed in Scopus and published in those same four years:

For example, the 2022 CiteScore counts the citations received in 2019-2022 to articles, reviews, conference papers, book chapters, and data papers published in 2019-2022, and divides this by the number of these documents published in 2019-2022.

 

It is calculated annually and available on Scopus. Scopus contents are reviewed and selected by an independent Content Selection and Advisory Board (CSAB), an international group of researchers with journal editor experience, based on their selection criteria.

 

Use and limitations

Use
  • Similar to JIF, CiteScore measures average citations to papers published in a journal, which becomes a fairly popular choice, especially among journals not holding a JIF.
limitations
  • Similar to JIF, concerns over using citations to represent research quality also apply, e.g., no indication of the large variation in citation levels across subjects or the skewed distribution of citations.

 

Access

Scopus: http://find.lib.hku.hk/record=alma991012748039703414

 

  1. Click on "Sources"
  2. Select "Title" or "ISSN" from the drop down list
  3. Enter the title or ISSN to search
  4. Click on the journal title to access its profile

    Screen capture 1 to 4
     
  5. On the journal profile page, find the latest CiteScore on the right hand side.

    Screen capture 5

 

 

References

  • Declaration on Research Assessment (DORA). (2024). Guidance on the responsible use of quantitative indicators in research assessment. DORA. https://doi.org/10.5281/zenodo.10979644
  • How are CiteScore metrics used in Scopus. https://service.elsevier.com/app/answers/detail/a_id/14880/supporthub/scopus/
  • Mingers, J., & Leydesdorff, L. (2015). A review of theory and practice in scientometrics. European Journal of Operational Research, 246(1), 1-19. https://doi.org/10.1016/j.ejor.2015.04.002

TOP Factor

TOP Factor

TOP Factor (Transparency and Openness Promotion Factor) is a metric that reports the steps that a journal is taking to implement open science practices, practices that are based on the core principles of the scientific community. It is an alternative way to assess journal qualities, aiming to improve over traditional metrics that measure citations. Journals are scored based on ten different criteria, e.g., availability of data and policies on preregistration. The criteria can be found here: https://www.cos.io/initiatives/top-guidelines.

 

Use and limitations

Use
  • It provides alternative metrics to journal quality on open science practices.
  • The underlying data and the evaluation rubric are transparent.
limitations
  • Journals might have opted not to support the TOP Guidelines for reasons such as fitting a one-size guideline to all, lack of plan for revision, and dichotomization of research results into statistically significant or not.
  • Potential refinement includes revising explanatory guidance intended to enhance the use, understanding, and dissemination of the TOP Guidelines; and clarifying the distinctions among different levels of implementation.

 

Access

TOP Factor: https://topfactor.org/

 

  1. Simply key-in the journal title for searching OR
  2. Conduct an advanced search by standard, discipline, or publisher

 

 

References

  • Lash, T. L. (2022). Getting Over TOP. Epidemiology, 33(1). https://journals.lww.com/epidem/fulltext/2022/01000/getting_over_top.1.aspx
  • Mayo-Wilson, E., Grant, S., Supplee, L., Kianersi, S., Amin, A., DeHaven, A., & Mellor, D. (2021). Evaluating implementation of the Transparency and Openness Promotion (TOP) guidelines: the TRUST process for rating journal policies, procedures, and practices. Research Integrity and Peer Review, 6(1), 9. https://doi.org/10.1186/s41073-021-00112-8
  • TOP Factor. https://www.cos.io/initiatives/top-guidelines
  • Woolston, C. (2020, 5 February 2024). TOP Factor rates journals on transparency, openness. Nature Index. https://www.nature.com/nature-index/news/top-factor-rates-journals-on-transparency-openness

     

     

Other metrics

Other metrics are also provided by various databases.

Here are some examples:

Journal Citation Reports (Web of Science)

Access: http://find.lib.hku.hk/record=HKU_IZ61507704370003414

Indicators Definition Guide
5-Year Journal Impact Factor The average number of times articles from the journal published in the past 5 years have been cited in the JCR (Journal Citation Reports) year https://incites.help.clarivate.com/Content/Indicators-Handbook/ih-5-year-jif.htm
Eigenfactor Based on
1.) the number of times articles from the journal published in the past five years have been cited in the JCR year, and
2.) which journals have contributed these citations so that highly cited journals will influence the network more than lesser cited journals
https://incites.help.clarivate.com/Content/Indicators-Handbook/ih-eigenfactor.htm
Journal Citation Indicator (JCI) A field-normalized metric representing the average category-normalized citation impact for papers published in the prior three-year period. https://clarivate.com/blog/introducing-the-journal-citation-indicator-a-new-field-normalized-measurement-of-journal-citation-impact/
 

Scopus

Access: http://find.lib.hku.hk/record=HKU_IZ61518360550003414

Indicators Definition Guide
SCImago Journal Rank (SJR) The average number of weighted citations received in the selected year by the documents published in the selected journal in the three previous years https://www.scimagojr.com/help.php#understand_journals
Source Normalized Impact per Paper (SNIP) Measuring contextual citation impact by weighting citations based on the total number of citations in a subject field https://blog.scopus.com/posts/journal-metrics-in-scopus-source-normalized-impact-per-paper-snip