Make sure that while limiting your search you do not exclude an important aspect of your subject!
In catalogues and databases without controlled vocabulary use the search terms you found during the orientation on your topic as keywords.
Try all the variations and different combinations of search terms, using exact phrases, Boolean operators, truncations and wildcards.
Most databases use controlled vocabulary to describe the subject of a publication. To get the best search results you need to use subject headings from this vocabulary.
This means you need to match your keywords to the correct subject headings for the database you want to search. Most databases provide indexes or a thesaurus to help you find the correct subject headings.
|Keyword||CINAHL subject heading||Medline Subject heading|
|Heart attack||Myocardial Infarction||Myocardial Infarction|
|Distance learning||Education, Non-traditional||Education, Distance|
|Electronic patient record||Computerized Patient Record||Electronic Health Records|
You can also start by doing a basic search with your own keywords, select publications relevant to your research question from the search results and look at the subject headings added to those publications.
Select the appropriate subject headings and use these to start a new search.
Combine the subject headings using Boolean operators to fit your research question.
If you do this correctly you will find more relevant literature on your topic; even if the subject is not part of the title of a publication or if the publications is written in a different language.
The thesaurus indicates which terms are broader or more general (BT= Broader terms), which terms are narrower or more specific (NT= Narrower terms) and which related terms (RT) can be used to search the database.
You can use the search operators AND, OR and NOT to combine search terms. These are the most commonly known and used operators.
The operators AND and NOT limit the number of results from a search. The operator OR does the opposite; it increases the number of results.
To see how this works, take a look at The Boolean machine. Move your cursor over the operators AND, OR and NOT to see how they determine your search.
You can also combine more than two search terms. Use brackets to indicate the priority. For example (Money OR inflation) AND banking.
Truncation (or wildcard symbols) can be used to broaden your search and include different spellings.
To do this, you shorten the search term to a word stem and, depending on which database you are using, you type either a question mark or asterisk after the word stem. The results will then include various endings and spellings.
If you search with environ*, the results will include publications with ‘environment’, ‘environmental’ and ‘environmentally’ in the text and/or title.
A question mark replaces a letter in a word; the results include British as well as American spellings.
For example, if you search with organi?ation, the results will include the British English spelling (organisation) as well as the American English spelling (organization).
If you search with labo?r, the results will include ‘labour’ as well as ‘labor’.
You can search for a specific expression or concept (e.g. “social media”).
To do this:
These actions will depend on the database you are using. Use the Help function for guidance.