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Online Tutorials for Health Science Library Resources: A Guide

Online tutorials and videos for PubMed, NCBI, ToxNet, Embase, Ovid Web of Science, Cochrane Databases, SAS, SPSS, Stata, Office, iWork, Boolean operators



  • AND combines two different terms (keywords) and retrieves only those records that contain both terms. The result is always narrower when you use AND.
  • OR combines two similar terms (keywords) and retrieves records that contain either one of them. The result is always broader when you use OR.
  • NOT excludes records containing the second term (keyword). Use NOT very carefully as it may eliminate what you really want.

Clinical and Health Research Databases

What is MEDLINE?

NLM has been indexing biomedical information since 1879. Index Medicus MEDLINE is the predecessor of a printed index called Index Medicus, which became a database knows as MEDLINE.  MEDLINE is available free to the public in PubMed, but the same database is also available in many other free and proprietary search engines.  The Matas Library supports PubMed, OvidSP, and  While each database has the same overlapping core, there are differences between each one.  Choose the database that has features and search support that meet your needs.

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