Data Extraction and Quality Assessment
Two investigators (D.F.B and J.R) independently screened all titles, abstracts and manually searched the full text versions of all pertinent studies that fulfilled the inclusion criteria. References of the relevant studies were independently reviewed for potential identification of further studies. Two investigators (D.F.B and J.R) independently assessed the quality items. Disagreements were resolved by consensus. Quality assessment of all included studies was done by using the 6 domains of the Cochrane tool for assessing risk for bias of RCTs.