Baldassarre 2017.

Study characteristics
Methods	RCT
Participants	Preterm infants (28 to 33 weeks' gestational age; birth weight 700 to 1750 g and appropriate to gestational age) within 24 hours of first enteral feeding (and whose mother did not plan to exclusively breast feed)
Interventions	Extensively hydrolysed casein infant formula (n = 33) Standard cow's milk‐based preterm infant formula (n = 35)
Outcomes	Enteral intake (mL/kg/d) during first 14 days after birth Feed intolerance measures (abdominal distension, regurgitation/emesis, feedings withheld ≥ 4 hours, or bloody stools) Necrotising enterocolitis Invasive infection
Notes	University of Bari‐Policlinico Hospital, Neonatology and Neonatal Intensive Care Unit, Department of Biomedical Science and Human Oncology, Bari, Italy Trial dates: 2014 to 2016 Trial registration: clinicaltrials.gov/ct2/show/NCT01987154 Further information provided by investigators (August 2017)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated
Allocation concealment (selection bias)	Low risk	Sealed opaque envelopes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"Double‐blind"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"Double‐blind"
Incomplete outcome data (attrition bias) All outcomes	Low risk	60/68 enrolled infants completed trial and contributed to outcome analysis
Selective reporting (reporting bias)	Unclear risk	Protocol not available
Other bias	Unclear risk	Funded by Mead Johnson Nutrition