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Systematic Reviews

Identifying Search Limits/Exclusion Criteria

Criteria Questions to Ask Advice from Cochrane Handbook for Systematic Reviews
Time Period Will your review be restricted by year of publication, or is it important that you cover all years? “Date restrictions should be applied only if it is known that relevant studies could only have been reported during a specific time period, for example if the intervention was only available after a certain time point.”
Language Should you restrict to English language publications only? “Whenever possible review authors should attempt to identify and assess for eligibility all possibly relevant reports of trials irrespective of language of publication. No language restrictions should be included in the search strategy.”
Publication Type Are you restricting your search by publication type? “Format restrictions such as excluding letters are not recommended because letters may contain important additional information relating to an earlier trial report or new information about a trial not reported elsewhere.”
Geographic Considerations Are there any geographic considerations to include in your search strategy? For example, if you were researching Chinese herbal medicine you would need to consult Chinese literature.