Akisu 2001.

Methods	Single centre, randomised controlled trial conducted in one NICU in Izmir, Turkey. Study period: July 1988 to January 2000
Participants	23 infants < 35 weeks' GA with ECHO‐confirmed PDA Ibuprofen: 12 infants, mean (SD) GA 32.1 (1.2) weeks; BW 1706 (187) grams; 5 girls, 7 boys; 9 born by C/S, 2 born vaginally, 10 had RDS, 7 received surfactant. PDA was diagnosed on day 3.9 (0.5) Indomethacin: 11 infants, mean (SD) GA 31.9 (1.3) weeks; BW 1645 (190) grams; 6 girls, 5 boys; 8 born by C/S, 3 born vaginally, 8 had RDS, 7 received surfactant. PDA diagnosed on day 3.5 (0.6)
Interventions	Ibuprofen: via an oro‐gastric tube (10 mg/kg as the initial dose followed by 5 mg/kg 24 and 48 hours later) Indomethacin: via an oro‐gastric tube (0.2 mg/kg for 3 doses at 12‐hour intervals) 2 neonates in the ibuprofen group and 3 in the indomethacin group required a second treatment with the same drug
Outcomes	PDA closure; diuresis; serum creatinine; thrombocyte count; gastrointestinal haemorrhage; IVH; sepsis; mortality
Notes	Study published in Turkish. No information provided about funding of the study
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Single centre, randomised controlled trial. No other information provided
Allocation concealment (selection bias)	Unclear risk	Allocation concealment ‐ no information provided
Blinding of participants and personnel (performance bias) All outcomes	High risk	Indomethacin and ibuprofen were administered at different time points
Blinding of outcome assessment (detection bias) All outcomes	High risk	Indomethacin and ibuprofen were administered at different time points
Incomplete outcome data (attrition bias) All outcomes	Low risk	Outcomes reported for all randomised infants
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