The Cochrane Library provides "high quality evidence for health care decision making" using criteria for conducting its systematic reviews. Within Cochrane Library, there are six resources containing evidence or reviews of healthcare and health policy:
More information about what is included in What's in the Cochrane Library? (PDF)
The Cochrane Library has three search interfaces: keyword, advanced, and PICO search. Each of these interfaces looks at the same pool of information and that information is all connected by Medical Subject Headings (MeSH) vocabulary terms. Always begin your search by looking up keywords in the MeSH browser from the Advanced Search screen:
Keyword searching is available on every page of the Cochrane Library in the upper right corner. There is also a drop-down list for more options. Using MeSH terms will get the best results.
The advanced searching interface has tabbed layers.
The advanced "Search" tab lets you search by many fields using the drop-down menu on the left of the search bar including keyword, author name, and DOI. You can also add search terms using the plus-sign button under the drop-down menu and add limiters like publication year and content type using the blue "Search limits" button on the bottom right.
The "Search manager" tab allows you to build and save searches using the same fields as the "Search" tab, but instead of being to the left of the search box they are to the right in the menu that is exposed when you click the "S" button. The publication year and content type limiters are also available from the far right "Limits" button. You can also search for MeSH subject headings within this page and add them directly into your search of the database by clicking the "MeSH" button to the right of the search bar. You cannot run searches from this tab, but with a free Cochrane account you can save your searches here.
The newest search interface allows you to mark your search terms as "Population" or "Outcome" when you are performing structured PICO searches. This interface is still in beta testing, so if you use it and have time you can give them feedback on how to improve it.
The results of your searches are displayed underneath the search boxes after you click "Run search." There are two parts to the results interface: the filters (left) and the list of results (right).
The filters on the left are limits that you can add to refine your search. You will probably want to only see results from the past 6 years and results that are in languages that you can interpret or translate. The results list is displayed in a tabbed window where they are grouped by which collection they were in. Sometimes this can be correlated to what type of evidence is contained. For example, "Cochrane Reviews" are systematic reviews, "Trails" are Randomized Controlled Trials (RCTs), and "Cochrane Protocols" are standard operating procedures (SOPs) for performing research.
More information about the features of the Cochrane Library can be found in the Cochrane Library User Guide (PDF)