“…Of these, we excluded 24 studies [9, for the following reasons: seven were abstracts [16,21,22,24,25,27,31], five presented mortality from one trial [28,29,32,33,38], three did not include a meta-analysis [19,26,34], three pooled non-randomised trials [20,35,37], and six were updated by more recent reviews (Additional file 1: Table S4) [9,17,18,23,30,36]. Nineteen systematic reviews provided 33 meta-analyses that satisfied the eligibility criteria of our overview [8,[39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56]. Table 1 presents the characteristics of the included systematic reviews and meta-analyses.…”