
Filters are ways to narrow your results. Common filters are publication dates, species, article language, study type, and article type. They may be prominent or available by clicking an "Advanced Search" hyperlink.
Some databases also allow users to display results by relevancy or most recently published.
TIP: Unless you are looking for landmark studies or the background information concerning your PICO, you may find that the filter that is most handy will be the "year" filter (it may be referred to by many names: published year, date, publication years, etc.)
Determine if your topic is best served by literature that has been published within a certain timeframe. Common ranges are within the past 5 years, 3 years, or even only the past year. Custom dates are often available as well.