Subject headings are a sophisticated tool that help you when you're undertaking a structured, in-depth search. They are set terms a particular database uses for concepts discussed in articles, no matter how the concepts are described. So articles mentioning 'lung cancer' would be assigned the subject heading 'lung neoplasms', as would articles mentioning 'lung tumours', or 'lung carcinomas'. By finding suitable subject headings for the concepts you are interested in, you will retrieve mainly relevant results right from the outset of your search.
The easiest way to find a suitable subject heading in CINAHL is to make sure the 'Suggest Subject Terms' box has a tick in it, type your first concept into the search box, then click on 'Search':
You will then see a list of headings that CINAHL has suggested; choose the heading that most closely matches your concept, by clicking in the box next to it. You can use the page icon in the 'Scope' column to check CINAHL's definition of the term. This is on the far right of the page.
At this point, look at the box in the 'Explode' column along from the subject heading. Is it light gray, or a slightly darker gray, as in the 'Major Concept' column? If it's a slightly darker gray, this indicates the subject heading has narrower subject headings ('narrower terms') grouped under it. Narrower terms are more specific terms that are related to your subject heading, and they could be useful to include in your search, so it's a really good idea to go in and have a look.
As you can see above, our 'Accidental Falls' example has no narrower terms, as the box in the explode column is a light gray. But the following example, for the subject heading 'Patient Education', does include narrower terms, as the box in the 'Explode' column is a darker gray:
To see what the narrower terms are, click on the subject heading itself. You will then see your subject heading, with a number of other subject headings under it and indented to the right; these are our narrower terms:
All the narrower terms grouped with your subject heading can be included in your search, simply by clicking in the 'Explode' column alongside the subject heading, then clicking on the green 'Search Database' button at the right of the page:
If you don't think the narrower terms will be of any use to you, then don't click n the 'Explode' box, and go back to your subject headings page, by clicking on 'Back to terms List', on the left of the green ribbon that goes across the page:
If you can't see any subject headings you like on the first subject headings page, click on the 'More' link at the bottom of the page, and keep going through the subject headings.
Because you may not always find a suitable subject heading, then you can use keywords instead. See the Keywords & Truncation tab of this guide for information on this.
Once you've selected your subject heading (and subheadings, if you want; see the Subheadings tab for more information), click on the green 'Search Database' button that appears at the right of the page.