These databases contain varying levels of evidence. Ranging from expert opinions to systematic reviews and meta analyses, these health sciences databases are the best place to start your search. Most of the information in these databases has been peer-reviewed, but most articles have not been evaluated by experts to determine the strength of the evidence. This is called unfiltered information.
You can also search for specific Publication Types or Article Types like Systematic Review, Meta-Analysis, Guideline, or Randomized Controlled Trials in Health Sciences Databases like CINAHL, PubMed, and ClinicalKey for Nursing.
search and selection methodology should be described well enough for another researcher to duplicate the process; 3) selected literature should be analyzed, not just summarized--articles and groups of articles compared, themes identified, gaps noted, etc.