Subhedar 1997.

Methods	Single‐centre randomised comparison of iNO, dexamethasone, combined therapy and control, using a 2 × 2 factorial design
Participants	42 preterm infants less than 32 weeks' gestation with "high risk" of developing BPD
Interventions	iNO initially administered at 20 ppm and weaned if effective (n = 20) or control (n = 22). Dexamethasone at 1 mg/kg/d for 3 days, followed by 0.5 mg/kg/d for 3 days (n = 21) (3 infants received a lower dose), or no steroids (n = 21)
Outcomes	Primary outcome was survival without bronchopulmonary dysplasia. Secondary outcomes included duration of ventilation, intraventricular haemorrhage and other neonatal complications.
Notes	Initially planned 88 participants
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated random numbers
Allocation concealment (selection bias)	Low risk	Masking of allocation: yes
Blinding (performance bias and detection bias) All outcomes	High risk	Masking of intervention: no Masking of outcome measurement: no
Incomplete outcome data (attrition bias) All outcomes	Low risk	Completeness of follow‐up: yes
Selective reporting (reporting bias)	Unclear risk	No registration or protocol found
Other bias	High risk	Terminated early because frequency of adverse primary outcome was close to 100% in all groups
Funding Source	Low risk	Government agency and local funds, some support from industry