Using Databases for Your Research

• How to Access Cochrane at the University of Dayton

• Before you start searching, keep in mind . . .

• Keywords - How to Find & Use

• Controlled Vocabularies 

  • Medical Subject Headings (MeSH)

  • Trees & Subheadings

• Combining Searches Using Boolean Operators (OR, AND, NOT)

• Field Tags

• Proximity Searching in Cochrane

• Applying Filters

• Truncation

• How to Access Full Text

• More Information

• Cochrane Tipsheet (pdf)

Save your search in a document, export your results to a citation management software (Endnote, Zotero, etc.), and create a custom account in the database:

• By saving your search, your strategy will be reproducible for another time and properly documented.

• Explore options and instruction for citation management here, and find tips on how to export results.

• To save searches and create alerts in Cochrane, create an account. Sign up for a Cochrane account by clicking here, or by clicking on the same link in the upper-right hand corner of the Cochrane homepage. Once logged in, go to the “Search Manager” tab (the tab directly to the right of the default “Search” tab). Towards the bottom of this page there is a purple drop-down menu labelled “Save this search” with an option to “Save as.”

• To create an alert for a saved search strategy, click on the “View saved searches” link. In the window that opens, select the checkbox for “e-mail alert” for the individual search.

• Keyword terms can be single words or phrases. In Cochrane, keywords should be entered in the “Search” tab

• Use quotes around all phrases to ensure that the phrase is searched instead of each word individually. (e.g. “public health”)

• For more possible search terms, visit the MeSH database and look at the "entry terms" listed for each MeSH record. These are synonyms, alternate forms, and other closely related terms generally used interchangeably with the preferred term.

• To find additional ideas and/or synonyms, consult controlled vocabularies in other subject databases. For example, Embase has a controlled vocabulary called Emtree. Emtree records contain synonym lists similar to the "entry terms" in a MeSH record.  The Emtree synonym list often contains European spellings/variations.

Locate Controlled Vocabulary (MeSH)

• Cochrane relies on Medical Subject Headings (MeSH) from the National Library of Medicine, composed of a controlled vocabulary of biomedical terms used to describe the subject of each journal article. To access the hierarchical listing of terms, click on the “Medical Terms (MeSH)” tab or use the MeSH icon in the Search Manager.

• After typing in a term in the MeSH search box, matches to the MeSH thesaurus will be displayed along with structured trees that show the hierarchical relationships among related terms.  A summary of search results from different Cochrane databases will also be displayed.

• Once you have selected your MeSH tree options, you can run it as a search by clicking the “Add to Search Manager” link. It will then be present  in the “Search Manager” tab (second from the left). 

Trees & Subheadings

• MeSH trees displayed in Cochrane allow you to visualize where your MeSH term sits in the hierarchy of terms and shows any branches off of your term. Selecting “Explode all trees,” allows you to search for your term and any terms that branch from it. Selecting “Single MeSH term (unexploded),” allows you to just search for your MeSH term without branches. If your MeSH term is part of multiple trees, you can select the specific trees you want to search by selecting “Explode selected trees.”

• A second search box gives you the option to "Select subheadings / qualifiers." Any MeSH can be made more specific by the addition of  subheadings. These appear as a drop down menu similar to what’s described above for  the “Enter MeSH term” box.

• A comprehensive and systematic search of the Cochrane Library includes both controlled vocabulary and keyword terms (i.e. free text, natural language, and synonyms).

• Boolean operators are used to combine search terms. In Cochrane, you can use the operators AND, OR, and NOT.

• Boolean operators MUST be used as upper case (AND, OR, NOT).

  • OR--use OR between similar keywords, like synonyms, acronyms, and variations in spelling within the same idea or concept

  • AND—use AND to link ideas and concepts where you want to see both ideas or concepts in your search results

  • NOT—used to exclude specific keywords from the search, however, you will want to use NOT with caution because you may end up missing something important.

• Go to the “Search Manager” page to combine searches. This is where your search history is located during your search session, and the plus and minus icons on the left side of the screen allow you to add/remove searches.

• To save searches and access your search history, sign up for a Cochrane account by clicking here.

From the Search Manager tab, you can use field tags to specify where the database looks for the search term. In Cochrane, first type the search term and then the field tag preceded by a colon. e.g.  Cardiology :ti looks for cardiology in the title

:ti — Searches the Title field

:ab — Searches the Abstract field

:kw — Searches the Keyword field

:au — Searches the Author field

:so — Searches the Source field

:pt — Searches the Publication Type field

• Cochrane allows for proximity searching through the use of two operators (NEAR or NEXT), along with a number to indicate the proximity of the words.

• Proximity search using NEAR: Use NEAR/ with a number to indicate proximity of terms either before or after each other. For example, “antidepressant NEAR/10 narcolepsy” looks for the word antidepressant within 10 words of narcolepsy. The default proximity value for the operator when no number is entered is 6.

• Proximity search using NEXT: Use NEXT to match terms that appear next to each other. E.g. cholera NEXT treat* would return “cholera treatment.”

• Note that the apostrophe within a term is treated as a space. To search for adjacent words in a term such as Down's Syndrome, the best approach is to use NEAR instead of NEXT.  The search parameter to use in this case would be: down* NEAR/2 syndrome.

• Hyphenated terms: Hyphens are treated as a space with an associated NEXT operator. The term heart-related will match the same results as heart NEXT related. E.g. evidence-based NEXT medicine.

​Cochrane will default your search results to Cochrane Reviews only. These results are often far fewer than the non-Cochrane Review results. To see all results, either click on the "Search Limits" link beneath the search boxes on the main Search page, or go to the column to the left of the search results. At the top of the results list, there should be tab options to select which type of study type you wish to see (Cochrane Reviews, Cochrane Protocols, Trials, Editorials, Special Collections, etc). Toggling between these will show different portions of the total results.

• In Cochrane you can use a * at the root of a word to find multiple endings. For example:

arthroplast* will return arthroplasty, arthroplasties, arthroplastic, arthroplastics, etc.

mobili* will return mobility, mobilization, mobilisation, mobilize, etc.

• You can also use a ? as a wildcard to search for letter variants within a word (e.g. wom?n finds women and woman)   

Additional examples of how truncation can be used (in combination with adjacency searching) 

Cochrane provides full text access to all featured Cochrane Reviews directly within the database. For other research publications found within Cochrane (Other Reviews, Trials, Methods Studies, etc), simply click on the item in Cochrane and it should list options for accessing it externally. If Cochrane does not point you to a website providing full text, then try searching for the item from PubMed or from another medical database (Web of Science, etc).

• General principles on searching in any database

• Cochrane Library Training: https://www.wiley.com/customer-success/cochrane-library-training-hub — includes Cochrane Library Reference Guide and the Cochrane Library training hub

• More detailed information about MeSH vocabulary is available at (https://www.nlm.nih.gov/mesh/) or (https://www.nlm.nih.gov/mesh/intro_retrieval.html)

This content was adapted from “Cochrane Library Search Tips” (created in 2018 at Welch Medical Library) by Simon Robins, which is licensed under Creative Commons 4.0 License, CC BY, and from content found on Welch Medical Library's Nursing Resources Guide which is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License attributable to the Welch Medical Library.