Comparison 1. Lower versus higher targeted oxygen saturations (no subgroups).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Death or major disability by 18 to 24 months corrected age (aligned definition)	5	4754	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.98, 1.10]
2 Death or major disability by 18 to 24 months corrected age (trialist defined)	5	4751	Risk Ratio (M‐H, Fixed, 95% CI)	1.07 [1.00, 1.14]
3 Death to 18 to 24 months corrected age	5	4873	Risk Ratio (M‐H, Fixed, 95% CI)	1.16 [1.03, 1.31]
4 Major disability by 18 to 24 months corrected age (aligned definition)	5	3867	Risk Ratio (M‐H, Fixed, 95% CI)	1.01 [0.93, 1.09]
5 Major disability by 18 to 24 months corrected age (trialist defined)	5	3864	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.94, 1.14]
6 Death to discharge	5	4958	Risk Ratio (M‐H, Fixed, 95% CI)	1.16 [1.03, 1.31]
7 Severe retinopathy of prematurity or retinal therapy (trialist defined)	5	4089	Risk Ratio (M‐H, Fixed, 95% CI)	0.72 [0.61, 0.85]
8 Patent ductus arteriosus requiring medical or surgical treatment	5	4928	Risk Ratio (M‐H, Fixed, 95% CI)	1.00 [0.95, 1.06]
9 Necrotising enterocolitis	5	4929	Risk Ratio (M‐H, Fixed, 95% CI)	1.24 [1.05, 1.47]
10 Cerebral palsy with GMFCS level 2 or higher at 18 to 24 months corrected age	5	3877	Risk Ratio (M‐H, Fixed, 95% CI)	1.02 [0.79, 1.32]
11 Blindness	5	3875	Risk Ratio (M‐H, Fixed, 95% CI)	1.13 [0.65, 1.97]
12 Severe hearing loss	5	3869	Risk Ratio (M‐H, Fixed, 95% CI)	1.02 [0.73, 1.43]
13 Proportion of infants re‐admitted to hospital up to 18 to 24 months corrected age	1	295	Risk Ratio (M‐H, Fixed, 95% CI)	1.08 [0.93, 1.26]
14 Weight (grams) at discharge home	1	295	Mean Difference (IV, Fixed, 95% CI)	‐52.0 [‐214.25, 110.25]
15 Weight (kilograms) at 18 or 24 months corrected age	1	280	Mean Difference (IV, Fixed, 95% CI)	0.80 [‐0.24, 1.84]
16 Days of endotracheal intubation	2	1386	Mean Difference (IV, Fixed, 95% CI)	0.28 [‐1.16, 1.72]
17 Days of CPAP	3	2526	Mean Difference (IV, Fixed, 95% CI)	‐0.04 [‐1.38, 1.30]
18 Days of supplemental oxygen	3	2507	Mean Difference (IV, Fixed, 95% CI)	‐8.78 [‐12.02, ‐5.54]
19 Supplemental oxygen requirement at 36 weeks postmenstrual age	5	4175	Risk Ratio (M‐H, Fixed, 95% CI)	0.87 [0.81, 0.94]
20 Days on home oxygen	2	237	Mean Difference (IV, Fixed, 95% CI)	‐24.17 [‐57.99, 9.66]
21 Quantitative Bayley III scores (Composite Cognitive Score (CCS))	2	1892	Mean Difference (IV, Fixed, 95% CI)	0.55 [‐0.91, 2.00]
22 Quantitative Bayley III scores (Composite Language Score (CLS))	1	903	Mean Difference (IV, Fixed, 95% CI)	0.20 [‐2.03, 2.43]