diseases and those with long periods between exposure and eР» Time and cost effective with relatively fewer subjects pared to other observational methodsРLimitations:Р» Unable to provide the same level of evidence as randomized controlled trials as it is observational in natureР» Difficult to establish the timeline of exposure to disease eР•“N=1” trialsР AdvantagesР » Easy to manage Р » Inexpensive Р Limitations:Р» Findings difficult to be generalized to the whole population Р» Weakest evidence due to the number of the subjectР7、Р• Synthesis of evidence pletely dependent on:Р » pleteness of the literature search (unavailable for foreign studies)Р » The accuracy of evaluation Р·There are situations in which no answer can be found for the questions of interest in RCTs and database analyses.
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