Salas 2015.

Methods	RCT
Participants	72 Infants (36 in each group) with gestational age between 23 0/7 and 28 6/7 weeks receiving minimal enteral nutrition (defined as enteral feeding volume < 24 mL/kg/d) and intravenous fluids during the first week after birth were eligible. Infants with major congenital/chromosomal anomalies and those considered to have a low likelihood of survival in the opinion of the clinical team were excluded.
Interventions	Gastric residual volume was checked with a syringe before each feeding, with the infant in the supine position. If the gastric residual volume was more than one‐third of the previous feeding or > 2 mL, if the clinician’s decision was to continue enteral feeding, then: Intervention or re‐feeding group: gastric residual was re‐fed Comparison or fresh‐feeding group: gastric residual was discarded followed by feeding of fresh human milk or formula Slightly greenish or dark yellow gastric residuals were re‐fed. Gastric residuals containing blood on visual inspection by bedside nurses were not re‐fed. Small gastric residual volumes (< one‐third of previous feeding volume or < 2 mL) were managed according to clinician preference (usually re‐fed unless bilious or with blood). When an infant in the re‐feeding group had large gastric residual volumes for 3 consecutive feedings, the gastric residual volume before the fourth feeding was discarded and fresh human milk/formula was given. The amount of gastric residual did not influence the amount of feed given at the next feeding. The allocated intervention was continued until full enteral feeding was achieved and maintained for 2 consecutive days
Outcomes	Primary outcomes Time to achieve full enteral feeding (defined as ≥ 120 mL/kg/d) for 2 consecutive days Diagnosis of SIP and/or NEC and/or death between birth and 120 days or discharge, whichever was earlier Secondary outcomes Number of TPN days Time to regain birth weight Number of episodes of feeding intolerance (defined as interruption of enteral feeding for > 12 hours) Duration of hospital stay
Notes	Enteral feeding was administered as intermittent bolus gavage feedings every 3 hours. Either expressed human milk (preferred) from the mother or high‐protein full‐strength preterm formula (24 cal/oz) was used for feeding. Donor human milk was not used. Feeding advancement was done by 20‐mL/kg/d increments until the total volume reached ≥ 120 mL/kg/d. If human milk is the source of enteral nutrition, human milk fortifier is added once the enteral feeding volume reaches 100 to 120 mL/kg/d
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomly assigned to one of the intervention groups following simple randomisation procedures
Allocation concealment (selection bias)	Low risk	"using sequentially numbered, opaque, sealed envelopes. Sealed envelopes were opened in sequential order after informed consent was obtained"
Blinding of participants and personnel (performance bias) All outcomes	High risk	The intervention was not masked
Blinding of outcome assessment (detection bias) All outcomes	High risk	The intervention was not masked
Incomplete outcome data (attrition bias) All outcomes	Low risk	All 72 infants were taken into account for the outcomes of mortality before discharge and NEC. The babies who had developed NEC or died were excluded from the analysis for all other outcomes
Selective reporting (reporting bias)	Low risk	Study protocol had been published. All proposed outcomes were reported
Other bias	Low risk	Nil

NEC: necrotising enterocolitis.

RCT: randomised controlled trial.

SIP: spontaneous intestinal perforation.

TPN: total parenteral nutrition.