There are two ways to search for your concepts. Most databases default to keyword searching which uses natural language (i.e. breast cancer). There is also the option of searching Subject Headings, an authoritative term (i.e. breast neoplasms) that applies consistency among database content.
The best searches combine both Keyword and Subject Heading terms.
Read on to find out more!
Definition:
*This chart represents some of the keywords that are captured in a single subject heading.
You may have heard of MeSH (Medical Subject Headings). This is the controlled vocabulary developed by the National Library of Medicine. Many databases use MeSH including Medline (through OVID or PubMed), ProQuest Nursing & Allied Health, and the Cochrane Library.
How do I find Subject Headings?
Finding a subject heading varies depending on the database. Many databases have a thesaurus you can browse, and others may automatically suggest a subject heading when you enter a keyword.
Here's a tip!
Do a keyword search in a database and click on any articles that look relevant to your topic. The subject headings are usually hyperlinked at the bottom of the citation. Write down any subject headings that you think would be relevant for your search.
Along with Subject Headings, it’s also important to search by keyword.
Definition:
Keywords are the normal, plain language words used within a text.
Databases may search for a keyword in the content’s title, abstract, author, subject headings, journal title, full-text and more.
Search Keywords to Capture Recently Added Articles and Trends
Recently Added Articles: Sometimes it takes a bit of time for an indexer to assign Subject Headings to an article that has just been uploaded into the database. Since keyword searching will look in places such as the abstract, you will still be able to capture these new articles in your results.
New Trends: In addition, new words for emerging technologies, diseases or abstract concepts are not recognized by databases, which is why it is also important to search by keyword.
For example, in 2014 a new strain of the flu virus was identified in Asia, the bovine viral diarrhea virus. Articles on BVDV exist in Medline, but the database only recognizes them by looking at keywords.
How to Search for Keywords
Searching for keywords is a lot of work. You need to keep synonyms and homonyms in mind.
Synonyms: If you want to see every article available on a topic, you will need to think of every synonym that an author could possibly use. A perfectly innocent word like migraine has 35 synonyms in Medline. Some of these might be obscure to the non expert. This is why it's nice to combine keywords with Subject Headings. You don't need to stress as much that you have every synonym possible when searching with Subject Headings.
Migraines could be referred to using a less specific term, such as 'sick headache'; or by older terms such as a 'status mingrinosis'; or by a very specific term for one aspect of the disease, such as 'Alice in Wonderland syndrome.'
Homonyms: While depression seems perfectly concrete, a keyword search will also find articles on Cortical Spreading Depression, economic crises, and even compressions in CPR.
IMPORTANT:
Databases require phrases to be placed within double quotes, i.e. "kidney allograft". Without the double quotes, the database will search for the words individually.
Here's a tip!
Most databases have operators to help you with your search. A common one is called truncation, usually represented with an asterisk. When the asterisk is placed at the root of a word, all possible endings will be searched.
Example: adolescen* retrieves adolescent, adolescents, adolescence
Read the "Help" section of the database you are searching to find out what other useful operators you can use during your search.
416-864-5059
hslibrary@smh.ca
Follow @SMHealthSciLib
