Skip directly to: Main content  |  Main navigation

Claude Moore Health Sciences Library

Claude Moore Health Sciences Library Print Friendly Version of:
http://www.hsl.virginia.edu/collections/ebm/pyramid.cfm

Individual Portal Pages:

Information Mastery: Navigating the Maze

Pyramid

Types of EBM Information Sources Available, with Examples
(ranked according to the "Usefulness of Medical Information Equation")

The Secrets of the Pyramids

Search Protocol:

  • The pyramid above is a graphical representation of how to search efficiently for the best evidence. The examples of EBM information sources in this pyramid are placed from top to bottom according to the "Usefulness of Medical Information" equation illustrated below:
Usefulness = Relevance x Validity
? Work
  • This model suggests that you start your search at the top of the pyramid with systematic reviews from the Cochrane Database of Systematic Reviews. Cochrane is small in the amount of information it currently contains, making it easier to search, but large in the validity and relevance of the information it contains for answering therapeutic questions.
  • Depending on the success of your search in Cochrane, you would work your way down the pyramid of resources in order of decreasing relevance/validity and increasing work, until you find an answer.
  • Journal articles form the base of the pyramid because they represent large amounts of "unrefined" information, and the burden of determining the validity and relevance is up to the user. The work part of the "Usefulness Equation" is also very high for journal articles as it may require a lengthy MEDLINE database search to locate them.

Searching and Alerting Tools:

  • With the ever-growing number of pre-validated information sources available, clinicians now need two tools to help them identify information that is highly relevant and valid: an Alerting Tool and Searching Tool.
  • A good Alerting Tool would notify the clinician whenever new relevant information becomes available. An example of such a tool would be Daily InfoPOEMs - a companion product to InfoRetriever (a searching tool) from the company InfoPOEMs: The Clinical Awareness System.
  • A good Searching Tool would search multiple databases or sources of information simultaneously and present the results in an easy-to-use format based on relevance and validity.
  • The pyramids below illustrate several such Searching Tools. Not all search tools are equal, and when using one it helps to evaluate it by asking the following questions:
    1. Does it search information sources that have a high usefulness score (higher on the pyramid)?
    2. Does it search multiple information sources simultaneously?
    3. Does it rank its search results according to usefulness (top of pyramid sources listed first)?
    4. Does it answer the highest percentage of questions in the least amount of time?

Pyramid

Search Tool: Ovid's Evidence-Based Medicine Reviews (EBMR)
(sources ranked according to the "Usefulness of Medical Information Equation")

Search Tool: InfoRetriever
(sources ranked according to the "Usefulness of Medical Information Equation")

Pyramid

Search Tool: TRIP Database
(sources ranked according to the "Usefulness of Medical Information Equation")

Pyramid

Search Tool: SUMSearch
(sources ranked according to the "Usefulness of Medical Information Equation")

Return