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CINAHL Guided Exercise: 2. Subject Heading Search

2.  Subject Heading Search

In this module you will learn how to find relevant Subject Headings for our first, or P, element.

Remember, for each PICO element we will perform both a Subject Heading and a Keyword search. Each type of search has different advantages that will make our search more relevant.

Let's begin with the Subject Heading.

What is a Subject Heading?

  • Subject headings describe the topic of a paper, similar to tags or hashtags.
  • They are pre-defined, controlled vocabulary that standardizes and pulls together synonyms, alternate spellings, and different word endings.
  •  In CINAHL these are known as CINAHL Subject Headings.
  • Subject headings are arranged in a hierarchy, from broader to more specific.
  • Subject experts add these subject headings using the most specific and relevant heading available.
  • Depending on how substantially this topic is covered in the paper, these are added to either the Major Subjects or Minor Subjects fields.

Tip: Beginning a search design with a subject heading is good practice as the information in the Scope Note and Tree will help create the subsequent keyword search.

For this guide we will consider the research question: "In infants, does using disposable diapers vs. cloth diapers affect the likelihood of diaper rash?"

Start building your search using the first PICO element, the concept for Problem/Population.  For this part of the exercise we will use the search term: infants.

Step by Step: Subject Heading Search

Identify the Subject Heading

  1. Select Suggest Subject Terms in the checkbox above the search box.
  2. In the search box, type Infant.
    • This will find potential CINAHL Subject Headings. We will use the Scope note and Subject Tree to choose the best one.
  3. Click Search.
    • You will now see a list of potential subject headings.
    • It shows one or more possible subject headings: Infant is one of several options and seems most relevant.
    • To confirm that Infant is the best term, review the Scope note and Tree.
 
Video demo: Identify the Subject Heading

Review the Scope note and Tree

To confirm that the Subject Heading Infant is correct, we will look at additional information: Scope notes and Tree.

  1. Click on the yellow bubble Scope note icon on the right to view the scope note.
    • From the definition, Infant seems appropriate.
  2. Click on the linked term Infant for the Tree View.
  3. Find the heading Infant in bold and review its place in the tree.
    • There are more specific relevant terms indented beneath it. You can view these by clicking the + icon.
  4. Select Infant by clicking the checkbox to the left. A blue column appears.
    • Note that the Explode tool is selected. This includes the more specific terms in our search.
  5. Leave the Explode tool selected.
  6. Leave Include All Subheadings selected in the blue column. See "Subheadings" Tip for more detail on how these can be effective.
  7. Scroll to the end of the blue column for additional information about the subject term. In this case, it reminds us to include the plural form infants in our future keyword search.
  8. Click Search Database at the top right.
Checking the Scope Note
more information...
 
Video demo: View the Scope Note and Tree

Explode and Major Concept Tools

Explode

The Explode tool selects the selected heading as well as any narrower terms that are indented below it. This is a useful shortcut, for example, Explode Canada will find papers that are tagged with the heading of Canada as well as any that are tagged with the Provinces. If some of the terms are not relevant to your question, uncheck explode and select only the terms that match your question.

In our example, selecting Explode for Infant will include all the narrower terms indented below it in the list. These describe specific subsets of our patient population, "Infant."

Major Concept

The Major Concept tool will only search for those articles where the topic is the main point of the paper. Where a subject heading has been designated as a major concept of the paper, it is listed under Major Subjects on the document's profile and identified by a MM in the search history.

  • Major Concept can be useful when needing a few very relevant papers on a single topic
  • It is usually not used when doing a comprehensive search for a Systematic Review, nor when there will be other search elements in the strategy.

As we will be searching additional PICO elements, we will keep the search broad and not use Major Concept for Infant

 
Video demo: Explode and Major Concept

Subheadings

Subheadings allow you to choose a specific aspect of your topic. For example, adding Trends will find papers about the changes over time that diapers have had or may have.
  • Include All Subheadings is selected by default. In most cases, this is the best option.
  • They are useful when searching for an aspect of a particular topic. E.g. diapers/adverse effects finds papers about the negative impact of diapers.

Find the Subject Heading for your P Concept

Following the steps outlined above, find the most appropriate subject heading for your first concept.

TIPS:
  • From the list of potential subject headings[1], decide what subject heading you will use for your search by checking the Scope note:
    • Does the definition, or scope, match my concept?
    • Check the blue column for a year of entry and does it cover the time period I need?
    • Are there any other subject headings to consider for my topic?
    • Does the list under Used For cover my topic?
    • Do these words suggest synonyms I can use in my keyword search?
  • When checking the Tree you will be looking for the most specific subject heading for your topic
    • Are there other broader or narrower subject headings that match your P concept?
  • Select any subject headings that apply to your P concept. [Note: if all are relevant use the Explode tool]
[1] The term displayed at the bottom in black is the Keyword form (infant (Search as Keyword)), this will be addressed in the next Step.
[Tip: Use your PICO sheet to track your decisions and to note any clues to additional search terms.]