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Research Metrics

A guide for research impact tools, databases, and metrics

Article Metrics

Evolving Definitions of Article Metrics

Article metrics have traditionally been defined by the number of citations an article receives. In recent years, however, scholarly communities such as SPARC and the Public Library of Science have advocated for additional metrics to be considered, alongside citation counts, when measuring the impact of an individual article or publication.

According to SPARC, article metrics should ideally "aggregate a variety of data points that collectively quantify not only the impact of an article, but also the extent to which it has been socialized and its immediacy." SPARC labels this definition of article metrics as Article-Level Metrics (ALMs). Researchers are encouraged to use traditional data points such as citation counts, along with other types of data points such as usage, mentions, and Altmetrics to quantify both the "scholarly visibility" and "social visibility" of an article. These different types of data points are visualized (right), and they are also discussed below. We encourage Hopkins researchers to follow this model when conveying article metrics.

*The Public Library of Science (PLoS) was the originator of Article-Level Metrics and they provide a robust set of resources and tools to facilitate the understanding and application of ALMs at https://plos.org/publish/metrics/.

Commonly Used Article Metrics

Individual articles can be measured by the following indicators:

Citations

Measures which articles have cited a particular article. Several different databases provide citation counts to discover this for individual publications.

Usage

Downloads and page views from the publisher's site, as well as from open access repositories when an article is published twice.

Captures

Number of times bookmarked on CiteULike, shares on Mendeley, reads or downloads on ResearchGate.

Mentions

Number of appearances in blogs, news articles, wikipedia articles, and other similar online content.>

Social Media Mentions

Number of posts featuring the article on Twitter, Facebook, LinkedIn. See the Alternative Metrics section of this guide for more information.

Citation Tracking

Citation tracking is used to assess the impact of articles or authors based on the number of times the article or authors have been cited by others. Citation tracking can be useful when assessing an author's impact in a field or determining seminal papers on a topic. The graphic below shows the most highly-cited articles in the field of early mobility over a time span of decades. See example below demonstrating highly-cited articles in a field over time.

 

example of citation tracking data visualization

Comparing Different Platforms for Citation Tracking

There are three primary resources used for citation tracking: Google Scholar, Scopus, and Web of Science. Google Scholar is a free resource provided by Google, while the other two are vendor-maintained bibliographic literature databases. Each one has its strengths and weaknesses. Use the table below to determine which resources is right for you.

 
Google Scholar
Scopus
Web of Science
Strengths
  • Excellent resource for finding cited references
  • It's free!
  • May find more obscure references
  • Better open access journal coverage
  • Better foreign language coverage
  • Better Social Sciences & Arts/Humanities coverage
  • Allows for advanced searching
  • Excellent search limits by discipline
  • The most well-known and most used resource for citation analysis
  • Citation analysis goes back further than Scopus
  • Allows for advanced searching
Weaknesses
  • Often pulls irrelevant content in search results, including results from predatory publishers
  • Few options for sorting results and advanced searching
  • Citations only go back to the year 1960
  • Prioritizes Elsevier articles and publishers
  • Weaker Arts/Humanities & Social Sciences content than Scopus
Vendor
 Google Elsevier Clarivate Analytics
Coverage
  • Books from Google Books
  • Dissertations
  • Peer-reviewed articles
  • Patents
  • Case law
  • Trade journals
  • Slide presentations
  • Gray literature
  • Newsletters
  • Syllabi (if cited by scholarly articles)
  • Over 21,500 peer-reviewed journals
  • Over 360 trade publications
  • Over 4,200 open access journals
  • Over 120,000 book titles
  • Over 7.2 M conference papers
  • Over 27 M patent records
  • Over 12,000 peer-reviewed journals
  • Over 1,300 open access journals
  • 30,000 books with 10,000 added annually
  • Over 2.6 M chemical compounds and 1 M chemical reactions
  • 148,000 conference titles with 12,000 added annually

"Article Metrics and Citation Tracking Graphic" by Simon Robins and Carrie Price, Welch Medical Library is licensed under CC BY-NC 4.0

Citation Tracking Table adapted from the University of Michigan's library guide, Research Impact Metrics.

Using Different Platforms for Citation Tracking

Use the instructions below to see where to find the cited by number in Google Scholar. Note that each platform shows the same article, and each resource shows a different number. This is because each resource pulls from different data to arrive at a definitive number, so there will always be variation.

Google Scholar

Run a search in Google Scholar. The number of citations displays under the citation information. Click on the "Cited by..." to view the citations that cite that article. 

Use the instructions below to see where to find the cited by number in Scopus. Note that each platform shows the same article, and each resource shows a different number. This is because each resource pulls from different data to arrive at a definitive number, so there will always be variation.

Scopus
Run a search in Scopus. The number of citations displays to the right of the citation listing. Click on the "Cited By" column number to view the citations that cite that article. 

Use the instructions below to see where to find the cited by number in Web of Science. Note that each platform shows the same article, and each resource shows a different number. This is because each resource pulls from different data to arrive at a definitive number, so there will always be variation.

Web of Science
Run a search in Web of Science. The number of citations displays to the right of the citation listing. Click on the "Times Cited" number to view the citations that cite that article. 

Further Reading

  • Falagas, M. E., Pitsouni, E. I., Malietzis, G. A., & Pappas, G. (2008). Comparison of PubMed, Scopus, Web of Science, and Google Scholar: strengths and weaknesses. FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology, 22(2), 338–342. https://doi.org/10.1096/fj.07-9492LSF
  • Kokol, P., & Vošner, H. B. (2018). Discrepancies among Scopus, Web of Science, and PubMed coverage of funding information in medical journal articles. Journal of the Medical Library Association: JMLA, 106(1), 81–86. https://doi.org/10.5195/jmla.2018.181
  • Kulkarni, A. V., Aziz, B., Shams, I., & Busse, J. W. (2009). Comparisons of citations in Web of Science, Scopus, and Google Scholar for articles published in general medical journals. JAMA: The Journal of the American Medical Association, 302(10), 1092–1096. https://doi.org/10.1001/jama.2009.1307
  • Minasny, B., Hartemink, A. E., McBratney, A., & Jang, H.-J. (2013). Citations and the h index of soil researchers and journals in the Web of Science, Scopus, and Google Scholar. PeerJ, 1, e183. https://doi.org/10.7717/peerj.183
  • Tananbaum, G. (2013). Article-Level Metrics: A SPARC Primer. https://sparcopen.org/our-work/article-level-metrics/

Vendor Training

Scopus

Scopus offers tools to help you make informed decisions about important articles in your field. This short video demonstrates analyzing your search results.

 

Web of Science

Similarly, Web of Science offers many of the same types of analyses. This video describes how to analyze your search results.