Bone 1989a

Methods	n = 147, 13 centres Allocation concealment: central randomization Baseline similarity: age, sepsis Blinding: caregivers Cointerventions: not described Withdrawals: In Bone 1989b, 1/50 control patients died shortly after randomization but before the start of study drug infusion. This patient was included in the analyses of 30 day and 6 month mortality. No treatment patient was withdrawn. Additional withdrawals were not described in Slotman 1992. Losses to follow‐up: In Bone 1989b, one patient was lost to follow‐up before 30 days and was classified as a survivor. The treatment group of this patient was unclear and we therefore retained this patient in our analyses. Another two control patients and three treatment patients were lost to follow‐up between 30 days and six months. These patients were not included the the analysis of six month mortality. No additional losses to follow‐up are described in Slotman 1992.
Participants	Inclusions: Risk factor for ARDS: trauma, post surgery, sepsis; bilateral CXR infiltrates; P/F less than or equal to 150 mmHg on PEEP = 0 cmH2O or less than or equal to 200 mmHg on PEEP > 0 cmH2O Exclusions: Severe lung disease, liver or renal failure; severe head injury; high dose steroids
Interventions	Continuous IV PGE1, maximum dose 30 ng/kg/minute (43.2 mcg/kg/day) for 7 days, or placebo
Outcomes	30 day mortality: RR 1.15 (RR 0.86 to 1.55), based on data from 147 patients Six month mortality: RR 1.18 (95% CI 0.89 to 1.57), based on data from 96 patients Adverse events leading to discontinuation of therapy not reported Other safety information: hypotension (treatment: 10/50 patients, control: 7/51 patients); dysrhythmias (treatment: 10/50 patients, control: 5/51 patients); flushing (treatment: 2/50 patients, control: none); diarrhoea (treatment: 6/50 patients, control: 1/51 patients)
Notes	Data from 147 patients were reported in Slotman 1992, of whom data from 101 patients were reported in Bone 1989b. We counted these two publications as one study. We extracted 30 day mortality data from Slotman 1992 and six month mortality and adverse events data from Bone 1989b.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Low risk	A ‐ Adequate