Library:Search strategy example

From UBC Wiki

Design a structured search

  1. Develop a strategy based on your PICO concept analysis.
  2. Understand how different search engines function.
  3. Discover which subject heading or descriptors, and which keywords are best for each concept.
    • Use the thesauri in databases to decide which to use and to gather ideas for other terms.
      To start find a few good articles either from a reference list, or a search in Google Scholar or one of the databases, and check which subject headings or natural language they’ve used. (known as reverse engineering). The Scope Note in databases is another good place to find additional search terms. Add these to your search.
  4. Maintain a table of concepts and Search terms.
    • Expand this by looking at a few key articles’ subject headings, and the thesaurus scope notes for additional terms and synonyms. Also known as berry picking.
  5. Search each concept separately.
    • Create different result sets.
    • Combine like concepts with OR.
    • Combine different ideas with AND.
    • Apply Limits such as age, gender, publication date, language, type of study as a last step.
  6. Revise terms and strategies.
    • This is an iterative process; add new terms to each as they are found and re-search the databases.
  7. Save your search strategy to save time! - Make an account for each platform eg Ovid, Ebsco, Proquest


EXAMPLE:

A search question analyzed according to the PICO elements:
In stroke patients (P), do home visits by Occupational Therapists (I) improve activities of daily living (O)?
[The search was run in Medline on the Ovid platform]

  1. exp stroke/
  2. stroke.ti,ab.
  3. Brain infarct* or cva or cerebrovascular accident* or cerebral vascular accident*.mp.
  4. 1 or 2 or 3
  5. House calls/
  6. House call* or home visit*.mp.
  7. 5 or 6.
  8. Occupational therapy/.
  9. Occupational therap*.mp.
  10. 8 or 9
  11. 7 and 10
  12. 11 and 4
  13. Quality of life/
  14. "quality of life".mp.
  15. 13 or 14
  16. 12 and 15
  17. Limit 12 to yr=2007 to current

EXPLANATION:

Line/Set 1 The subject heading for stroke is “exploded” to include the more specific concepts listed under it in the Tree. This is a search using the Ovid platform and the search word is identifiable as a subject heading by the / on the end.
Line/Set 2: In Ovid the programming syntax is preceded by . In this case .ti,ab indicates that word stroke is looked for in the title and abstract.
Line/Set 3: The synonyms and their variant endings such as Brain infarct, CVA etc. are searched for in many places (.mp) – essentially the title and abstract. Using the truncation symbol * directs the search engine to find variant endings for example both the singular and plural versions.
Line/Set 4: The results of the subject heading and keyword searches in sets 1-3 are all combined with the operator OR to create all the results related to the P concept
Lines/Sets 5-10: These sets repeat the previous process for searching the I concept.
Line/Set 9 The truncation allows for therapist, therapists or therapy or therapies
Line/Set 11 Uses the AND operator to Instruct the search engine to look for results that reflect BOTH the house calls and the OT concepts
Line/Set 12 Uses the AND operator to Combine the P sets with the I sets
Lines/Sets 13-15 are the results for the O concept.
Line/Set 16 Combines the O with the results of P and I

[Note: This structured approach provides flexibility for adjusting the search when results are too low. For example, adding the O element in resulted in zero results. By going back to Line/set 12 suitable articles were retrieved.]

Line/Set 17 A set of results is limited to those articles published between 2007 and the present. Other limits which are available include gender, ages, language, study types etc.