CINAHL

Explode means that your results will include everything given this subject heading and also any more specific subject headings. Subject headings are like the branches of a tree with, for example, “neoplasms by site” subdividing into the different areas of the body that can get cancer “abdominal neoplasms,” “bone neoplasms” and so on. Indexers are instructed to index items by using the most specific subject headings they can. By clicking on the ‘breast neoplasms’ link you can see how the subject headings are organised and that there are more specific types of breast cancer.
 

When you choose a subject heading a new column will pop up asking if you want to specify subheadings. The default option is to include all subheadings and we recommend that you should do this. Subheadings narrow your search and get you fewer results. Subheadings allow you to indicate specific aspects of the CINAHL heading that are of interest. For example the complications of breast neoplasms.

You are also asked if you want the subject heading to be a major concept. Choosing this will also narrow your search so you get fewer results and so you need to consider if it is relevant for the type of searching that you are doing. Selecting Major Concept retrieves citations for articles and publications where the CINAHL Heading is a main focus. CINAHL typically assign three to four major concept headings to each publication. So although you will have fewer results they will be more relevant (but you may not see other relevant articles.)

If you tick both explode and major concept then you will retrieve references that have that subject heading, or the more specific headings, as their main topic.

Then click the green Search Database button to see the results.