Now that you've created a list of search terms and keywords, you need to organize them into meaningful search statements.
When you search electronic databases (such as a library catalog or an electronic index ), you cannot just type in your research question ("What risk factors are associated with polluted drinking water?"). Unlike some big, commercial search engines like Google, the electronic databases won't understand what you are looking for. You need to speak in a way they will understand.
One concept to formulate effective search statements is to use Boolean Operators (AND, OR, NOT) to connect your keywords and concepts, like this:
AND - narrows a search; Use to combine key concepts, for example: Water AND Pollution.
OR - broadens a search; Use to add concepts, for example: Pollution OR Water.
NOT - excludes search term(s). Use to eliminate a concept, for example: Water NOT Pollution. Use sparingly!
To practice Boolean Searching, go to Exercise: Boolean Operators.