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Evidence-Based Research

Things to Consider

Things to Consider

  • Your question needs to be relevant to the client's outcome and include only resources which are available.
  • Your question needs to be clear and focused in order to get relevant results. Remember, when you search databases you are talking to a machine, not another person. Use terms the machine will understand.
  • Consider how the terms you will be searching are labeled. They may be called something different by non-professionals or by different disciplines. You will likely want to include all of these various synonyms when searching.
  • You're initial question may be incomplete but as you search you will likely be able to refine your terms to make your question more complete.
  • Keep it simple. Don't try to answer multiple things at once. Stick with one question at a time.

Background v Foreground Questions

When to use the P.I.C.O. model...

Background questions concern general knowledge.   These types of questions generally have only 2 parts:

  • A question root (who, what, when, where, how, why) and 
  • A disorder, test, treatment, or other aspect of health care.   

Often these questions can best be answered by using a textbook or consulting a clinical database.

Foreground questions are specific knowledge questions.

  • Affect clinical decisions, including a broad range of biologic, psychological, and sociologic issues. 

These are the questions that generally require a search of the primary medical literature and that are best suited to the PICO format.

Answerable Question & Building Search Strategy


P - Patient or Population

I - Intervention

C - Comparison (if any)

O - Outcome

Search Strategy

  • Develop "answerable question" using PICO
  • Search one term or concept at a time
  • Consider all possible terms, including synonyms to describe the topic
  • Use OR to broaden your search
  • Use AND to narrow your search
  • Try different combinations of terms, particularly if limited retrieval
  • Review search results; critically appraise retrieved articles
  • Consider using limits for publication types, age, human, and evidence-based
  • Revise search as appropriate

*Shlonsky & Gibbs, 2004, call this COPES searching, Client-Oriented Practical Evidence Searching

    Finding EBP Articles in Databases

    Finding  EBP Articles to Answer PICO Questions

    To find evidence based research articles and to answer clinical questions in the PICO format (Population, Intervention, Comparison, Outcome) you can use the following limiters: