“…Findings show (see Figure 4 ) that 11 papers focused on NIV [ 13 , 18 , 38 , 42 , 44 , 49 , 52 , 54 , 57 , 58 , 59 ], 7 focused on IV [ 11 , 17 , 45 , 53 , 55 , 56 , 60 ] and a further 13 included both [ 25 , 29 , 37 , 39 , 40 , 41 , 43 , 46 , 47 , 48 , 50 , 51 , 61 ]. However, those patients on ventilation were often only part of the population included, and for those papers covering both forms of ventilation, it was not always possible to distinguish these patients in the findings.…”