Watterberg 2004.

Methods	Multi‐centre double‐blind randomised controlled trial
Participants	360 infants of 500 grams to 999 grams birth weight, needing mechanical ventilation, aged 12 to 48 hours Exclusions: major congenital anomaly, congenital sepsis, postnatal corticosteroids, triplet or higher‐order gestation
Interventions	Hydrocortisone 1 mg/kg/d 12‐hourly for 12 days, then 0.5 mg/kg/d for 3 days Control group infants received an equal volume of normal saline placebo.
Outcomes	Survival without BPD (oxygen at 36 weeks), physiological BPD, death before 36 weeks, death before discharge, BPD in survivors, durations of mechanical ventilation and oxygen, hospital stay, weight and OFC at 36 weeks, PDA, infection, NEC, GI perforation, major IVH (grade 3 or 4), cystic PVL, ROP, and open‐label corticosteroid therapy Longer‐term outcomes included neurosensory impairments (any of cerebral palsy, blindness, deafness, or developmental or motor delay, as assessed by Bayley Scales (MDI or PDI, respectively)).
Notes	Sample size estimate was 712, but the study was stopped early because of increased incidence of apparently spontaneous GI perforation in the hydrocortisone group.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random allocation, stratified by centre and birth weight (500 grams to 749 grams vs 750 grams to 999 grams), via a permuted block scheme with blocks of 6 in each stratum. Randomisation lists in each pharmacy in a sealed envelope
Allocation concealment (selection bias)	Low risk	Allocation concealment: yes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinding of intervention: yes
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinding of outcome measurements: yes
Incomplete outcome data (attrition bias) All outcomes	Low risk	Complete follow‐up: yes
Selective reporting (reporting bias)	Low risk	All prespecified outcomes reported