Romano‐Keeler 2016.

Methods	Open‐label, randomised, controlled trial
Participants	99 infants (48 intervention and 51 control) Inclusion criteria: gestational age < 32 weeks Exclusion criteria: refusal to participate, enrolment in competing studies, Spanish‐speaking only Setting: NICU, Monroe Carell Jr. Children’s Hospital at Vanderbilt, Nashville, Tennessee, USA From February 2013 to July 2014
Interventions	Oral priming with mother's colostrum ‐ 0.1 mL colostrum administered to each cheek every 6 hours for 5 days started in the first 48 hours of life (intervention) compared with no oral priming with mother's colostrum (control)
Outcomes	Salivary immuno‐peptides and oral microbiota Necrotising enterocolitis (Bell's stage 2 or 3) Late‐onset bacteraemia Days to enteral feeds at 100 mL/kg/d Days of antimicrobial exposure Length of hospital stay (days) Type of feeds at discharge
Funding source	Vanderbilt University Medical Center and Thrasher Fund and NIH/NIGMS (GM106143 (to JLW)), USA
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"preterm infants (< 32 weeks' completed gestation) were randomised by a numeric list generated a priori to receive oral priming with mother’s colostrum or no oral priming"
Allocation concealment (selection bias)	Unclear risk	No details were provided regarding allocation concealment
Blinding of participants and personnel (performance bias) All outcomes	High risk	The study was not blinded "Participating staff members were not blinded"
Blinding of outcome assessment (detection bias) All outcomes	High risk	The study was not blinded "Participating staff members were not blinded", and assessors were not described so presumably were also part of the clinical team
Blinding of outcome assessment (detection bias) Death before discharge to home	Low risk	The study was not blinded, but death is unlikely to be influenced by blinding
Incomplete outcome data (attrition bias) All outcomes	Low risk	All randomised infants were included in the final analysis
Incomplete outcome data (attrition bias) Length of hospital stay	Low risk	Length of hospital stay was available for all participants
Selective reporting (reporting bias)	Low risk	All outcomes described in the methods were reported in the results. The protocol is available at clinicaltrials.gov (NCT01776268)