Dyke 1995.

Study characteristics
Methods	Single‐centre randomised double‐blind placebo‐controlled trial
Participants	26 preterm infants (29 to 36 weeks) requiring mechanical ventilation for hyaline membrane disease Exclusion criteria: major congenital malformations
Interventions	Morphine group (n = 12): loading dose 100 mcg/kg over 30 minutes followed by continuous infusion 10 mcg/kg/hour Placebo group (n = 14): dextrose 5% Infusion continued until weaning from intermittent mandatory ventilation, or for maximum of 48 hours' therapy. Pancuronium allowed for infants not stabilised by ventilatory adjustment and markedly asynchronous with the ventilator (2/12 infants in morphine group, 3/14 in the placebo group)
Outcomes	Primary outcomes: heart rate, blood pressure, respiratory rate hourly; severity of respiratory distress; interaction of the infant with positive‐pressure ventilation Secondary outcomes: duration of oxygen therapy; ventilator therapy and hospitalisation; incidence of bronchopulmonary dysplasia, periventricular haemorrhage, and pneumothorax
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was performed by a computer‐generated list in the pharmacy
Allocation concealment (selection bias)	Low risk	Allocation concealment was adequate
Blinding of participants and personnel (performance bias)	Low risk	Caregivers were blinded to treatment
Blinding of outcome assessment (detection bias)	Low risk	Assessors were blinded to treatment
Incomplete outcome data (attrition bias)	Low risk	There was no loss to follow‐up
Selective reporting (reporting bias)	Unclear risk	Trial not registered; protocol not available
Other bias	Low risk	Study appears to be free of other sources of bias