Most library databases have inbuilt limits that allow you to refine the search to specified criteria, such as English language, date, publication type(s) etc.
The image below displays some of the limits from Ovid MEDLINE.
Search filters (AKA hedges) provide a search string that you can copy/paste at the end of your search. These can help to focus your search and retrieve more clinically relevant research from health science databases. Using search filters for a particular topic or methodology may improve your search sensitivity or decrease the number of irrelevant results. Explore the resources below to find one you need, or ask us for help.
TIP: Use filters with caution and always test before you finalise your search. Not all filters have been validated.
If you end up using a filter or adapting one, either way you'll need to cite and describe how you've adapted it in your search methods.