It is important to finalize your inclusion and exclusion criteria after finalizing your research question but before developing your search strategy. Well-defined inclusion/exclusion criteria
Types of criteria could include
Turning a research question into a search string is a multi-stepped process:
As you do test searches and read more relevant literature, you will be able to add additional keywords to your search concepts. It is recommended that you reach out to a librarian for assistance in generating keywords and mapping concepts to a controlled vocabulary.
Topic | Keywords Natural language |
Pubmed MeSH |
CINAHL Subject Headings |
Academic Search Complete Subject Terms |
obesity | obesity overweight obese morbidly obese |
"Obesity"[Mesh] "Obesity, Morbid"[Mesh] |
(MH "Obesity") (MH "Obesity, Morbid") |
DE "OBESITY" DE "MORBID obesity" |
heart disease | heart disease cardiac diseases heart disorders cardiovascular |
"Heart Diseases"[Mesh] | (MH "Heart Diseases") | DE "HEART diseases" |
stroke | stroke cerebrovascular accidents |
"Stroke"[Mesh] | (MH "Stroke") | DE "STROKE" |
Once all terms have been identified, you need to put them together in a search string. You can export your search strategy in addition to the results, to use in your search documentation.
A search string will generally look like:
(Topic A term 1 OR Topic A term 2) AND (Topic B term 1 OR Topic B term 2) AND (Topic C term 1 OR Topic C term 2)
If searching PubMed with our example research question, the search string would look like:
(obesity OR overweight OR obese OR "morbidly obese" OR "Obesity"[Mesh] OR "Obesity, Morbid"[Mesh]) AND ("heart disease" OR "cardiac diseases" OR "heart disorders" OR cardiovascular OR "Heart Diseases"[Mesh]) AND (stroke OR "cerebrovascular accidents" OR "Stroke"[Mesh])
The search string above was developed for PubMed. When adapting the string for another database, you want to have the strings operate as similarly as possible. You would replace the MeSH terms with the controlled vocabulary of the other databases used.
The search string above is searching with both keywords and MeSH terms. The MeSH terms will be searched in the MeSH field. The keywords will be searched in all fields, like the title, abstract, journal name, etc.
The PRISMA-S Extension documents all the required elements needed in your final, published article to ensure that your search is transparent and reproducible. It is recommended that you familiarize yourself with the checklist before finalizing your search strategy to ensure you document all the necessary information.