 Hi, my name is Alex, I'm a librarian at the University of Alabama, and in this tutorial I'm going to show you how to use PubMed's advanced search. The advanced search is useful simply because it gives you more options for controlling and refining your search. To really get the most of the advanced search, you need to have a decent understanding of two things, the search fields and the Boolean operators. The search fields just allow you to search in a more precise, controlled way. The default is sort of a grab bag catch-all, but you can narrow your search by choosing a specific field. There are way too many search fields to discuss in one video, but there are a few that I'll touch on. Mesh terms or subject headings are an extremely important concept in PubMed, but we'll do a deep dive on those and other tutorials. Text word, title, and title abstract are ones that I find quite useful. The title search field can be used in a couple ways. If you know an article's title already, you can paste it in and run a title search. Alternatively, if you have a key concept you're searching for, you could do a title search for it. Now every single result should have type 2 diabetes in the title of the article, which is just a way of narrowing your search. You can do the same thing with the title abstract field. This just makes it so the word COVID-19 will be in either the title of the article or the abstract, or both. Finally, a text word search just looks for that specific word or phrase in the text of the actual articles. That's a broader search than a title search. The advanced search really shines when you use Boolean operators in conjunction with field searching. The three Boolean operators are and, or, and not. It combines two or more search terms and narrows your search results. Or is best for looking for related terms and it expands your search results. Not simply excludes a certain search term. Quick examples of each. I'm looking for articles about the use of vitamin D in treating COVID-19. So I'll want to combine those terms with and. I'll start by looking for COVID-19 with the field title abstract. COVID-19 is the key part of all of this. I'll then combine that with a text word search for vitamin D. This will bring back articles that have COVID-19 in the title and or the abstract. And vitamin D will be mentioned in the full text of the articles. I'm going to show the or Boolean operator by searching for articles about COVID-19 again. We'll start by doing a title abstract search for COVID-19. But here I want to search for SARS-CoV-2, which is the coronavirus that causes COVID-19. They are fairly related terms so I'm going to add this to the search with or. This then finds articles that mention either COVID-19 or SARS-CoV-2 and the title or abstract. You might notice that the advanced search page contains your search history. They even give a search a number, which can be really useful in one specific way. You can simply type the number of a specific search into the search box and it will rerun that search. You could then add another search term to that. So in this case, I'm searching for vaccine and that one specific search, which is our search for COVID-19 or SARS-CoV-2. The final Boolean operator is not, which just gets rid of a search term. It's not hard to imagine where this might be useful. Searches often bring back results that aren't exactly what you were looking for. And that's all for this tutorial. We have other PubMed tutorials available if you want to learn more. And remember, if you have a question, just ask a librarian.