Unless the main component of your job is research, it’s a pretty good bet that you don’t spend all day at the library searching databases. And even if you do spend a lot of time helping library users search, you’re probably teaching and not using those advanced database searching skills you learned in library school. So when you have to sit down and actually do a complicated search, you’re probably panicking a little.
When you next find yourself in that situation, here are a few tips to help you extract every possible relevant result.
1. Write it out. Before you even start searching, look at the patron’s request and start brainstorming. Think of all possible terms, subject headings, synonyms, etc that might also be used to describe the topic. I like to make columns for each key term and list like terms under it.
2. Use the thesaurus. Every database has a thesaurus and it’s the best possible way to identify subject headings (especially the weird ones that only indexers would think to use) or alternate ways of phrasing or using a term. Since I search PubMed almost exclusively, I use the MeSH database, but your favorite database has a thesaurus too. Find it, use it, make it your best friend. If you’re really going comprehensive, you may even want to bust out the real thesaurus.
3. AND, OR, or NOT? Once you’ve gotten all your terms written down, it’s time to start building your search. We all learned Boolean logic in school, we probably use it everyday without thinking about it, but do we really understand it? Sure the basics are simple: dogs OR cats returns all results using dogs, cats, or both, while dogs AND cats only returns results that use both. Dogs NOT cats gives you results that are only about dogs and don’t mention cats at all. All that’s pretty simple; it only gets complicated when you start using parentheses. Speaking of…
4. Punctuation is your friend. You can link terms together using AND, OR, or NOT all day long, but unless you use parentheses, truncation symbols, and quotation marks correctly, you’re never going to get the most accurate set of results. It’s very important to pay close attention to where your parentheses are, especially if you are using a search builder like the one in the MeSH database. Double and triple check your search if it’s complicated otherwise it will take you a half hour to figure out why you have 3,000 results (true story). Every database is different so familiarize yourself with its truncation and key term rules. Asterisks and quotation marks are pretty standard, but it’s not always the case so be sure to follow your databases instructions.
5. Limit, Limit, Limit! I’m lucky that I search in a database that has pre set limits so I can move between result sets easily, but not all databases are so intuitive. Limiting by date, language, and journal type are the most common but don’t forget about making several subject headings major subject headings or excluding a term that keeps popping up with a well-placed NOT. Each search is different so you may have to tweak for a while until you get a list of manageable, relevant citations.
Do you do a lot of searching? What tips do you have to get more accurate citations?
*The search above was an actual search I did this morning. I was able to select several articles that worked out well for the requesting physician.