Comparison 1. Synthetic surfactant vs control.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Pneumothorax	5	2328	Risk Ratio (M‐H, Fixed, 95% CI)	0.64 [0.55, 0.76]
2 Pulmonary interstitial emphysema	4	2224	Risk Ratio (M‐H, Fixed, 95% CI)	0.62 [0.54, 0.71]
3 Pulmonary hemorrhage	5	2328	Risk Ratio (M‐H, Fixed, 95% CI)	1.44 [0.68, 3.05]
4 Patent ductus arteriosus	5	2328	Risk Ratio (M‐H, Fixed, 95% CI)	0.90 [0.84, 0.97]
5 Necrotizing enterocolitis	5	2328	Risk Ratio (M‐H, Fixed, 95% CI)	1.32 [0.76, 2.29]
6 Apnea of prematurity	4	2224	Risk Ratio (M‐H, Fixed, 95% CI)	1.20 [1.09, 1.31]
7 Intraventricular hemorrhage	4	2224	Risk Ratio (M‐H, Fixed, 95% CI)	0.88 [0.77, 0.99]
8 Severe IVH	5	2328	Risk Ratio (M‐H, Fixed, 95% CI)	0.84 [0.63, 1.12]
9 Bronchopulmonary dysplasia	5	2248	Risk Ratio (M‐H, Fixed, 95% CI)	0.75 [0.61, 0.92]
10 Neonatal mortality	6	2352	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.61, 0.88]
11 BPD or death at 28 days	4	2224	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.65, 0.83]
12 Retinopathy of prematurity in survivors examined	3	605	Risk Ratio (M‐H, Fixed, 95% CI)	0.93 [0.80, 1.09]
13 Severe retinopathy of prematurity in survivors examined	3	605	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.46, 1.17]
14 Mortality prior to hospital discharge	6	2352	Risk Ratio (M‐H, Fixed, 95% CI)	0.79 [0.68, 0.92]
15 Mortality at 1 year	4	2224	Risk Ratio (M‐H, Fixed, 95% CI)	0.80 [0.69, 0.94]
16 Lost to follow‐up	5	1819	Risk Ratio (M‐H, Fixed, 95% CI)	1.06 [0.85, 1.33]
17 Cerebral palsy in survivors examined	5	1557	Risk Ratio (M‐H, Fixed, 95% CI)	0.76 [0.55, 1.05]
18 Moderate ‐ severe cerebral palsy in survivors examined	5	1557	Risk Ratio (M‐H, Fixed, 95% CI)	0.75 [0.48, 1.16]