Patel 2000.

Methods	4 centre, randomised controlled trial in 4 NICUs (Hammersmith, Queen Charlotte's, St George's and St Mary's Hospitals, London, UK). Study period: January 1966 to December 1996
Participants	33 preterm infants with a haemodynamically significant PDA diagnosed clinically and on ECHO criteria Ibuprofen: 18 infants, median (range) GA 26.0 (23.9 to 35.00) weeks; BW 790 (620 to 2780) grams; postnatal age 8 (3 to 20) days; 9 boys, 9 girls Indomethacin: 15 infants, median (range) GA 26.7 (23.2 to 30.0) weeks; BW 838 (458 to 1377) grams; postnatal age 7 (3 to 21) days; 7 boys, 8 girls.
Interventions	Ibuprofen: 10 mg/kg IV as the initial dose followed by 5 mg/kg at 24 and 48 hours after the initial dose Indomethacin: 0.2 mg/kg as initial dose. 2 further doses were administered after 12 and 24 hours: infants aged 2 to 7 days at the time of the first dose received 0.2 mg/kg and infants ≥ 8 days received 0.25 mg/kg To prevent identification of the drug administered from the timing schedule, all infants received a fourth dose containing 0.9% saline: in the indomethacin group, 48 hours after the first dose and, in the ibuprofen group, 12 hours after the first dose; IV infusions of all drugs were performed over 15 minutes using an infusion pump
Outcomes	PDA closure rate, near‐infrared spectroscopy was used to measure changes in cerebral blood volume, cerebral blood flow, and cerebral oxygen delivery
Notes	Merckle GmbH donated the ibuprofen used in the study. No information on other funding
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information provided
Allocation concealment (selection bias)	Low risk	The Pharmacy Department at Queen Charlotte's Hospital performed randomisation in blocks of 12 for each hospital and provided all trial medication. All other personnel were blinded to the identity of the drug administered
Blinding of participants and personnel (performance bias) All outcomes	Low risk	See allocation concealment and intervention
Blinding of outcome assessment (detection bias) All outcomes	Low risk	See allocation concealment and intervention
Incomplete outcome data (attrition bias) All outcomes	Low risk	Complete follow‐up ‐ yes
Selective reporting (reporting bias)	Unclear risk	Study protocol was not available to us so we could not ascertain if there were deviations from the protocol
Other bias	Low risk	Appeared free of other bias