3.3.5 | Other outcome measures
Meta-analysis revealed a significantly lower incidence of pneumothorax and hsPDA in the MISA group than that in the control group (RR : 0.60, 95% CI : 0.39 to 0.93], p = .02, 9 studies14-19,21,22,26 (n = 1187) and RR : 0.88, 95% CI : 0.78 to 1.00, p = .04, 11 studies 14-19,21-25 (n = 1796), respectively). There were no significant differences between the two groups in the other neonatal complications, namely, pulmonary hemorrhage, retinopathy of prematurity (ROP) (>stage II or the need for treatment), intraventricular haemorrhage (IVH) (all grades), severe IVH (grade III or higher), and periventricular leukomalacia (PVL). For procedure-related outcomes, meta-analysis showed that MISA techniques increased the rate of surfactant reflux (RR : 2.12, 95% CI : 1.37 to 3.29, p = .0008, 5 trials16-18,21,26 (n = 576)), but did not increase the need for additional surfactant compared with the control group (RR : 1.17, 95% CI : 0.95 to 1.45, p = .15, 11 trials 15-22,24-26(n = 1658)). Sensitivity analysis was performed, and the heterogeneity of each outcome did not change significantly (Table 3).