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Bibliometrics and Altmetrics: Measuring the Impact of Knowledge

This guide includes information on which of the databases contain citation measures that can be used to gage either an author, article or journal impact.

Overview of Different Metrics

  Web of Science Scopus Google Scholar
Subject Focus
  • Science Citation Index
  • Social Science Citation Index
  • Arts & Humanities Citation Index
  • Health Sciences
  • Physical Sciences
  • Social Sciences
  • Life Sciences
Theoretically, all disciplines
  • 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
  • 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
  • Books from Google Books
  • Dissertations
  • Peer-reviewed articles
  • Patents
  • Case law
  • Trade journals
  • Slide presentations
  • Gray literature
  • Newsletters
  • Syllabi (if cited by scholarly articles)
Time Span Some journals from 1900 Some journals from the 1820s Some citations as far back as the 1660s and 1670s
Updated Weekly Daily Unknown but generally quick
  • Excellent search limits by discipline
  • The most well-known and most used resource for citation analysis
  • Citation analysis goes back farther than Scopus
  • Better open access journal coverage
  • Better foreign language coverage
  • Better Social Sciences & Arts/Humanities coverage
  • Excellent resource for finding cited references
  • It's free
  • May find more obscure references
  • Weaker Arts/Humanities & Social Sciences content than Scopus
  • Cannot search by date any earlier than 1960
  • Too much irrelevant content in search results
  • Few options for sorting results

Source: Citation Analysis Guide from University of Michigan. Authors: Paul Grochowski, Barbara Shipman, Deirdre Spencer, Sue Wortman.