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Citation Analysis: Citation Analysis

Citation Analysis

Citation Analysis - What is it?

Citation analysis is the study of the impact and  assumed quality of an article, an author or an institution based on the number of times works and/or authors have been cited by others.

Citation Analysis - Why use it?

    • To find out how much impact a particular article has had, by showing which other authors based some work upon it or cited it as an example within their own papers.

    • To find out more about a field or topic; i.e. by reading the papers that cite a seminal work in that area.

    • To determine how much impact a particular author has had by looking at his/her total number of citations.


Comparing Citation Analysis Sources

Here is a quick summary of what to expect from the three best known citation analysis tools.


Web of Science         Scopus               Google Scholar       
Subject Focus        

Science, Technology,
Social Sciences, Arts & Humanities

Science, Technology, Medical, Engineering, Arts & Humanities Medical, Scientific, Technical, Business,
Social Sciences, Arts & Humanities

Composed of 3 citation indexes:

  • Science Citation Index Expanded — back to 1900
  • Social Sciences Citation Index – back to 1956
  • Arts & Humanities Citation Index – back to 1975
  • Conference Proceedings -- back to 1990
  • Life Sciences, 4,873 titles
  • Health Sciences, 10,196 titles (including 100% coverage of Medline titles)
  • Physical Sciences > 9,800 titles
  • Social Sciences > 5,300 titles
  • Arts & Humanities, 1,439 titles; the majority of these titles go back to 2002
  • Selections from PubMed, IEEE, American Institute of Physics, proceedings of the National Academy of Sciences,, American Medical Association and other medicine journals, Ingenta, SpringerLink,Wiley Interscience, Cambridge journals, Taylor and Francis, Sage Publications, Blackwell-Synergy, OCLC First Search and others
  • Open access journals and pre-prints
  • Online dissertations and theses
Coverage Over 12,000 journals 19,500 active journals Unknown
Time Span
Some journal files going back to 1900; see above for more detail

44.4 million records, of which:

  • 23 million records include references going back to 1996 (78% include references)
  • 21 million pre-1996 records go back as far as 1823
Theoretically, whatever is available on the Web
Updated Weekly 1-2 Times a week Monthly on average
  • Deeper back-files especially for Science Journals
  • While controversial, its journal citation reports, impact factors, and h-index are most widely used.
  • More focused on U.S. research
  • Offers citation mapping for visual presentation
  • User friendly search interface
  • Broader coverage of journals (16, 500 versus 10,000 in WOS)
  • Downloadable reference list
  • More internationally focused than WoS
  • Includes more than 1,200 Open Access titles
  • Provides a more comprehensive picture of scholarly impact as it indexes non-traditional sources not covered by WOS and Scopus.
  • Includes peer-reviewed papers, theses, books, abstracts, and articles from academic publishers, professional societies, preprint repositories, universities, and other scholarly organizations
  • Better coverage of newer materials than both WOS and Scopus
  • International and multi-lingual coverage
  • Can lead to low citation counts due to errors in citations provided by authors, and different citation styles used by journals leading to poor indexing
  • Back-files are expensive
  • Citation tracking is limited to the relatively narrow time span of 1996+
  • Not very strong in Social Science and Arts & Humanities coverage
  • Limited search features
  • Inflated citation counts due to inclusion of non-scholarly sources such as promotional pages, table of contents pages, course readings lists etc.
  • Weeding irrelevant hits is time consuming
  • Difficult to export citations
  • No way to determine what sources, and time spans are covered.
  • Limited to what is available on the Web
  • May include non-scholarly citations like newspaper articles

Information on this page has been adapted from guides created at University of Michigan University of Ottawa Bibliotheque and University of Connecticut Library.


Much of the content of this guide is based on a guide created at University of Michigan Library and which can be viewed here. Thank you to the group that created that guide and allowed us to make use of the content for our own guide.

List of Titles Covered