Searching for subject headings
Subject headings are words or short phrases that are added to the records of references by the database. Subject headings use a ‘controlled language’, meaning there is only one word or phrase used to describe a specific concept. In theory, this means that every reference in Medline discussing breast cancer will have the ‘breast neoplasms’ subject heading regardless of whether the researcher has talked about breast tumours, breast tumors, mammary cancer, breast neoplasms, etc. Different Ovid databases have different subject headings which is why they need to be searched individually. For example, the subject heading for breast cancer in Embase is breast cancer rather than breast neoplasms.
However, not all concepts have an appropriate subject heading and there is a delay in adding the subject terms. Therefore, you should still search for keywords as well.
To search for subject headings, you should be in the Advanced Search tab and make sure you have the Map Term to Subject Heading box ticked below the search box.
This means that when you click search, the database will show you the subject headings that it thinks will be most appropriate for that term. If you are not sure if a subject heading is relevant then click on the i in the scope column to check the definition. This page is also useful as the Used For section will often give you other ideas of keywords to add to your search strategy.
Extra guidance
For more information, including video examples, please refer to our online guides listed below.
