Gerhardt 1977.

Methods	Randomised controlled trial
Participants	20 term newborn infants, born vaginally, whose mothers had received intravenous pethidine within 3 hours of delivery
Interventions	1. Intramuscular naloxone at 30 minutes of life (0.01 mg/kg): n = 14 2. Placebo: n = 10
Outcomes	Respiratory rate, tidal volume, minute ventilation, end‐tidal carbon dioxide tension, and the ventilatory response to inhalation of 4% carbon dioxide
Notes	NICU, North America, mid 1970s
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"By random number ... infants were selected", no further details reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Placebo‐controlled study but unclear if personnel were aware of infants' allocation to groups
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	Near‐complete follow‐up but 2 infants in each group were excluded post‐randomisation because "lung compliance values changed more than 25% between the two determinations"
Selective reporting (reporting bias)	Unclear risk	No protocol (though no reason to suspect selective reporting)
Other bias	Low risk	No reason to suspect any other bias