Systematic & scoping reviews

Building a search strategy on your topic

Once you have developed your PICO and well-formed clinical question you can begin to build your search strategy by translating the significant concepts of the PICO into a concept grid.

It is not necessary to include all of the PICO concepts in the search strategy. It is preferable to search for those concepts that can be clearly defined and translated into search terms. Although a research question may address particular populations, settings or outcomes, these concepts may not be well described in the title or abstract of an article and are often not well indexed with controlled vocabulary terms. It is useful to start with a broad search using the Population and Intervention elements of the PICO.

For example:

In middle aged women suffering migraines, is Botulinium toxin type A compared to placebo effective at decreasing migraine frequency?

Concept 1: Middle aged women Concept 2: Migraines Concept 3: Botulinium toxin type A

Alternative (similar) keywords

Authors often use different terms to describe the same concept. When searching it is important to consider alternative terms (synonyms) and spelling variations which may be used.

Think about:

  • Medical vs. Common terms e.g. Varicella Zoster / Chicken pox
  • Acronyms/Abbreviations e.g. COPD / Chronic Obstructive Pulmonary Disease
  • Generic vs. Brand name drugs e.g. Acetaminophen / Panadol
  • English vs. American terminology e.g. Tumour / Tumor
  • Broader vs. Narrower terms e.g. Obesity surgery / Bariatric surgery

Similar terms can be added to the grid beneath the relevant concept, for example:

Concept 1: Middle aged women Concept 2: Migraines Concept 3: Botulinium toxin type A
Women Migraine Botulinium toxin type A
Women Migraine disorders Botulinium toxins
Female Migraine headaches Clostridium botulinium toxins

Combining search terms with AND and OR

You can structure your search using AND and OR to combine your keywords:

  • AND - use to combine keywords that reflect different concepts e.g. women AND migraine
  • OR - use to combine keywords that reflect similar concepts e.g. woman OR female

Database search tips

  • Truncation (usually *) can be used to find alternate endings of a word e.g. educat* for educate, educated, education, educational etc.
  • Phrase searching (“ “) can be used to search for two or more terms as a phrase rather than individually e.g. “migraine headaches”
  • Wildcards (usually ?) can be used for spelling variations e.g. wom?n for woman and women
  • Title and abstract searching can be used to narrow search results and increase precision e.g. breast feeding.ti,ab. (Ovid databases)
  • Proximity searching can be used to achieve greater precision than phrase searching. Use the operators NEAR, NEXT OR ADJ . This allows you to retrieve records that contain your terms (in any order) within a specified number (n) of words of each other. e.g. community ADJ3 pharmacy.

Note: Truncation symbols, wildcard symbols and proximity operators can vary between databases. See the Help section in the databases to find out which symbols and operators are used.​

The following worksheet can be used to help in developing your search strategy:

Subject headings

Many databases use controlled terms, known as thesaurus terms or subject headings to categorise articles or records. Thesaurus terms vary for each database. In your search it can be helpful to use subject headings or thesaurus terms in addition to keywords. For more information see our video on Keywords vs Subject Headings. Click on the image below to view the video.

MeSH (Medical Subject Headings)

The National Library of Medicine controlled vocabulary thesaurus used for indexing articles for PubMed and Medline.

MeSH on Demand

Identifies MeSH terms in your submitted text (abstract or manuscript). MeSH on Demand also lists PubMed similar articles relevant to your submitted text.