Schweizer 1993.

Study characteristics
Methods	RCT
Participants	Preterm infants (formula fed)
Interventions	Extensively hydrolysed whey‐casein term formula (Alfare)* (n = 26) Non‐hydrolysed preterm formula (Prematil)* (n = 26)
Outcomes	Time to regain birth weight Time to full enteral feeding Mean number of high gastric residual volumes per day
Notes	Kinderklinik der Stadt, Klinlken, Dortmund Trial dates: 1991 to 1993 * Energy content of hydrolysed formula (70 kcal/100 mL) lower than control standard preterm formula (80 kcal/100 mL). Because trial did not report growth rates (the reason for specifying similar energy levels in comparison formulas), we made a consensus decision to include the trial
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information ‐ only abstract available
Allocation concealment (selection bias)	Unclear risk	Insufficient information ‐ only abstract available
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"Double‐blinded"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"Double‐blinded"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Outcomes reported for all participants
Selective reporting (reporting bias)	Unclear risk	Protocol not available
Other bias	Unclear risk	Funder: not stated