Filtered or secondary sources are summaries and analyses of the evidence derived from and based on primary sources (unfiltered). They provide an appraisal of the quality of studies and often make recommendations for practice.
What kinds of studies are relevant?
Use the handy metasearch tools below to find many different levels of evidence in one easy search:
Is there more synthesised evidence that busy practitioners can access to quickly make informed decisions about patient care?
The diagram below shows higher levels of synthesised evidence.
Clinical practice guidelines "are designed to support the decision-making processes in patient care . The content of a guideline is based on a systematic review of clinical evidence - the main source for evidence-based care". http://www.openclinical.org/guidelines.html