“…The PRISMA guideline was implemented in the study selection. Several studies were excluded due to several reasons, including inappropriate study design [ [11] , [12] , [13] , [14] ], inappropriate comparison [ [15] , [16] , [17] , [18] ] [ [15] , [16] , [17] , [18] ] [ [15] , [16] , [17] , [18] ], observational studies [ 16 , [19] , [20] , [21] ] and an abstract-only articles [ 22 ].…”