Mercer 2003.

Methods	Randomised controlled trial
Participants	Inclusion criteria Mother‐infant pairs < 32 weeks Vaginal or CS births N = 32 babies Exclusion criteria Obstetrician's refusal to participate, major congenital anomalies, multiple gestations, intend to withhold care, severe maternal illnesses, placenta abruption or placenta previa.
Interventions	Intervention: deferred cord clamping (DCC) Cord clamped at 30‐45 secs. At birth infant held 10 to 15 inches below the level of the placenta in vaginal deliveries or below the incision at CS N = 16 babies Comparator: ECC Cord clamped between 5‐10 secs after delivery N = 16 babies Additional information Gestational subgroup: < 32‐34 weeks' gestation Resuscitation with cord intact: not available Access to NICU: yes Length of delay: 30‐45 secs Baby placed: low Uterotonic: states 'Not given before cord clamping' but no information as to whether uterotonic was given after cord clamping UCM: n/a Comparison 1 DCC with neonatal resuscitation after cord clamping vs ECC (subgroup by gestation) Subgroup 1: < 32‐34 weeks' gestation Comparison 2 DCC with neonatal resuscitation after cord clamping vs ECC (subgroup by type intervention) Subgroup 2: DCC at < 1 min with baby low (+ gravity)
Outcomes	Primary outcome Mean arterial BP on arrival in the neonatal unit. Secondary outcomes Apgar scores, initial blood sugars, initial Hct, mean BP over 4 hrs of life, and 12 hrs, number of volume expanders in 12 hrs of life, SNAPPE II scores, serum bilirubin levels, days on ventilation or oxygen, IVH, suspected NEC, days on ventilation or oxygen, oxygen use at 36 weeks and at discharge, volume of blood transfusions
Notes	Setting: USA Dates: October 1998 to March 2001 Declaration of interest: not reported Trial funding source:“Sigma Theta Tau, Epsilon Chapter; University of Rhode Island Foundation and College of Nursing”. Further information: Confirmed NEC data are in the text in the paper and suspected NEC in Table 4. The 2012 publication reported suspected NEC by mistake, This has been rectified. J Mercer kindly provided additional information regarding this study reporting there were no baby deaths in this pilot study.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: “system of randomly prepared cards in sealed nontransparent envelopes."
Allocation concealment (selection bias)	Unclear risk	Quote: “system of randomly prepared cards in sealed nontransparent envelopes.”
Blinding of participants and personnel (performance bias) All outcomes	High risk	For this type of intervention blinding participants and the staff present at delivery to group allocation is not possible. Staff providing care may have modified their behaviour according to randomisation group.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	It is not clear whether lack of blinding would have had an effect on the outcomes measured. There was an attempt to achieve blinding for some of the outcomes assessed as staff were requested not to record group assignment on case notes.
Incomplete outcome data (attrition bias) All outcomes	Low risk	32 participants were randomised and all appeared to be accounted for in the analysis. 2 babies in the delayed clamping group were not treated according to protocol but  they were analysed according to randomisation.
Selective reporting (reporting bias)	Unclear risk	Assessment from published study report.
Other bias	Low risk	Groups appeared similar at baseline. Other bias not apparent.