Study selection
Search strategy yielded 514 potentially relevant records. After screening of titles and abstracts and evaluation of completed trials retrieved from ClinicalTrials.gov, seven full-text articles were assessed for eligibility and four [15-18] blinded, placebo-controlled RCTs were included in the meta-analysis. A flow diagram of the study selection process and specific reasons for exclusion are detailed in the Supplement (eFigure 1).