Pourarian 2015.

Methods	Randomised controlled trial conducted in the Neonatology Research Center, Shiraz Univeristy Medical Sciences, Shiraz, Iran. Study period: April 2012 to May 2013
Participants	Preterm infants with PMA < 37 weeks and postnatal age 3 to 7 days with ECHO diagnosis of a haemodynamically significant PDA
Interventions	Group I (high‐dose ibuprofen group) received 20 mg/kg PO ibuprofen as first dose followed by 10 mg/kg/dose after 24 and 48 hours Group II (normal‐dose ibuprofen group) received 10 mg/kg PO ibuprofen as first dose followed by 5 mg/kg/dose after 24 and 48 hours
Outcomes	Primary: Failure to close the PDA after the first course and after the second course. Secondary: Surgical ligation, ROP, bleeding disorders, GI bleeding, NEC, pulmonary haemorrhage, IVH (all grades) mortality, oliguria, serum BUN (mmol/L) after treatment, serum creatinine (mg/dL) after treatment, urine output (mL/kg/hr) after treatment, platelet count
Notes	No external funding was secured for this study
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	Cards in sealed opaque envelopes
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No information provided
Blinding of outcome assessment (detection bias) All outcomes	Low risk	The cardiologist performing the ECHOs was unaware of the infants' treatment assignments
Incomplete outcome data (attrition bias) All outcomes	Low risk	Outcome data provided for all randomised infants
Selective reporting (reporting bias)	Unclear risk	The protocol for the study was not available to us so we could not judge if there were any deviations from the protocol or not
Other bias	Low risk	Appeared free of other bias