CINAHL

You are probably familiar with PubMed's MeSH terms. MeSH stands for Medical Subject Headings and is PubMed's controlled vocabulary.  CINAHL calls their controlled vocabulary "Subject Headings."  Both are an excellent tool to locate on-topic articles.

A controlled vocabulary is a specified, pre-determined collection of terms (about 30,000 in this case). You cannot make up or add your own terms. Indexers (real live people!) read each article in CINAHL and tag them with a handful of these terms. Then, when we search on that term, all articles tagged with that term are retrieved.

Why use a controlled vocabulary? The magic lies in fact that the number of terms is restricted, which helps overcome the fact that these databases do not have an intuitive search like Google does. In Google, you can search "used cars for sale" and you'll get "used SUVs for sale," "used Jeeps for sale," etc.  These databases are not like that - you get articles that correspond to the terms you searched on. Using a controlled vocabulary helps overcome that.  

Example:  Let's say you're interested in articles about pressure wounds. You'd also be interested in articles that use the phrases "pressure sores," "pressure injuries," and "pressure ulcers." Since the databases aren't intuitive, if you search on "pressure wounds" and the article only uses "pressure injuries" you won't get that article (you didn't tell the database you wanted articles about pressure injuries!). You would have to create a search string that contains all of the phrases above.

However - the controlled vocabulary would have only one term for this topic. In CINAHL it's Pressure Ulcers. The indexers who read an article about "pressure injuries" would tag that article with the Subject Heading "Pressure Ulcers."  If the next article mentions only mentions "pressure wounds" it would also be tagged "Pressure Ulcers."  If the next articles says "bedsores" it would also be tagged with "Pressure Ulcers."

Then, by searching the subject heading "Pressure Ulcers," you will get articles that use the words "pressure wounds," "pressure sores," "pressure injuries," and "pressure ulcers" - and even bedsores.

If you'd like to use CINAHL's controlled vocabulary (similar to MeSH terms in PubMed), there are a few things to know before you begin. 

1) You have to create a search for each concept. For example, if we were looking for articles about pressure wounds in hospitalized patients, one concept would be "pressure wounds" and the other "hospitalized patients"  (if your question is formatted into a PICO question, quite often each letter is a concept).

2) To search for the correct Subject Heading, click "Subject Headings" and find the correct term (detailed steps below) which will fill in the first box in the image below. In the next box you will put all appropriate keywords.  Make sure you combine these boxes with OR. 

3) Repeat for the next concept, and continue until you have created a search for each one. Each search is saved.

2) Once you create search strategies for each concept, you will combine them using the Search History.  That way your articles contain words pertaining to ALL of the search strategies you created. 

How to Search using Subject Headings

Click on "CINAHL Subject Headings" in the green bar.

Type your term into the Search box and hit Browse.

Locate the right subject heading and select it by clicking the box in front of it.  The "Search Database" box to the right will auto-populate.  Click "Search Database" and CINAHL will bring you back to the main search page, having searched the database for all articles tagged with your subject heading, as you can see in the screen below.

Staying on that same page, type your  keywords in the second box, making sure you change the drop-down box AND to OR, then click Search.  It may seem counter-intuitive, but search on the subject heading as a keyword also, just to be sure you get those articles.

You have completed the search for your first concept!   Hit Clear, then repeat the steps for all remaining concepts - in this case, inpatients.

When you are finished with all of your concepts, hit Clear (very important; otherwise it gets included in the next step). Click Search History (under the last box).  All of your searches are there. Click the box in front of the completed searches and combine with AND.  Now we will get articles that include ALL of your topics.

You have now completed a search in CINAHL that includes CINAHL's Subject Headings (known as MeSH terms in PubMed, Cochrane and some others).  For information on how to export these, see the box to the left.

If you need a reproducible search strategy (e.g., for an systematic review) you'll need to do a few more steps. What you did above shows up with a search strategy of "S3 AND S4" which is not reproducible.  You'll need to copy the words that make up S3 and paste them into the first search box, then do the same for S4, and so on.  When all concepts are in the search boxes, hit Search.  Now you can go into Search History and copy the search string that has actual words and is therefore reproducible.