Fig. 1.

Flowchart depicting the process of conducting a systematic review about a health intervention considering the role of randomized and non-randomized studies. The explanations are portrayed as dark grey circles. See text for detailed description of each step. The grey area represents the steps that might be taken during the protocol development. Of note, as stated in the GRADE guidance, the assessment of the certainty of evidence should be made for each outcome evaluated in the review process.

*In most situations, the search strategy performed for the scoping review will be comprehensive enough to be used at this step; however, authors may prefer to run another search or include changes from the one in the scoping review.