In the last tutorial, I showed you how to formulate a focused question using the PICO model. Well the next step is to run individual searches in CINAHL for each of the concepts, or key terms, identified by the PICO model. The way CINAHL works best is that you do a separate search for each of the concepts, or key terms, and then combine and limit those searches in various ways to achieve the best and most relevant search result set. As I said in the last tutorial, I'm going to use this question as my example: "Does vitamin D supplementation reduce the risk of falls in older hospitalized patients?" From the PICO model, we know that these are the concepts we should search for in CINAHL. Let's start our search with the concept 'fall'. So, again, this is the main search page for CINAHL. So here I am going to leave everything as 'default', including this 'Suggest Subject Terms' box, which is one of the most useful features of this database. I'm going to type in 'falls'. Okay, I'm going to click on the 'Search' button... and I am then taken to the CINAHL headings page. This is where CINAHL gives you suggestions of subject terms based on the terms you entered. So I typed in 'falls', and it came up with these suggestions. Up on the top, we can see that the standard term in the CINAHL system for the concept 'falls' is 'accidental falls'. Now, why do we want to do that? Why can't we just use 'falls'? Don't they mean the same thing here? Well, first of all, the terms we enter in the search box could be ambiguous in their meanings. For example, the word 'fall' could mean many different things in the English language, and therefore, we need to restrict the meaning of the word to exactly what we mean by it, in this context. And, believe it or not, it is a very hard thing to do. On the other hand, people often use different words to describe the same concept. For example, for the concept 'hypertension', some authors may use the term 'high blood pressure', but others may use 'hypertension'. Running only a key word search for 'high blood pressure' will only give you references that specifically have the phrase 'high blood pressure' in them, and I will not get all those references that only have the term 'hypertension' in them. The vast number of synonyms in human languages create problems for running thorough searches in databases. To perform an exhaustive search, you have to find all synonyms for all concepts in your questions. So, all in all, we have at least two problems here: The ambiguity of the search terms we enter, and the vast number of synonyms in our languages. Now the CINAHL heading system is designed to solve these problems. CINAHL headings are a "standardized list of terms and their definitions used to describe the content of the articles indexed by CINAHL," and "they have very specific definitions". So in a CINAHL headings system, term ambiguity is not a problem. On the other hand, CINAHL indexers tried their best to assign the same CINAHL heading to all articles about the same concept. For example, articles on both 'high blood pressure' and 'hypertension' are assigned the term 'hypertension', which is the standard CINAHL heading for the condition. So, obviously, the most efficient way to search CINAHL is to use CINAHL headings. This way, I don't have to think of all the synonyms for the concepts in my question, and I don't have to worry about the ambiguity of the terms I enter. But how do we know if the search terms we put in the search box are standardized to CINAHL headings? Well, as we have seen here, the beauty of the system is that it can automatically map the search terms you enter to relevant CINAHL headings. For example, it says here that the closest match for the term we enter, 'fall', in the CINAHL heading system, is 'accidental falls'. That's why it's important to remember to leave the 'Suggest Search Terms' box checked in the previous screen. And I highly recommend that you always do your searches this way. You might also want to know that the 'Suggest Subject Terms' feature is also available under CINAHL headings, right here. So if I enter a term here, such as 'falls', it should suggest the heading 'accidental falls'. So, either way, I end up in the same screen. Now that we know how to use 'Suggest Search Terms' feature of CINAHL, we can then use the suggested CINAHL headings to do a better search, which is exactly what we're going to do in the next tutorial. I'll see you next time.