Gregory 1997

Methods	n = 51, 5 centres (see Notes) Allocation concealment: not described Baseline similarity: age, sepsis, organ failures Blinding: caregivers not blinded (no placebo) Cointerventions: only mode of mechanical ventilation standardized during study period Withdrawals: treatment (1/27), control (none) Losses to follow‐up: none
Participants	Inclusions: Risk factor for ARDS; mechanical ventilation; bilateral CXR infiltrates, P/F less than or equal to 200 mmHg, PEEP at least 5 cmH2O, compliance less than or equal to 50 ml/cmH2O, PAOP less than or equal to 18 mmHg; duration of ARDS 48 hours or less Exclusions: Chronic lung disease; lung cancer; AIDS; cardiogenic shock; head injury
Interventions	Intratracheal bovine surfactant (Survanta), 50 mg/kg for 8 doses, or 100 mg/kg for 4 doses, or 100 mg/kg for 8 doses, or standard therapy
Outcomes	28 day mortality (see Notes): RR 0.59 (95% CI 0.25 to 1.38), based on data from 43 patients Duration of ventilation (median days): 15 (50mg/kg for 8 doses group), 10 (100 mg/kg for 8 doses), 10 (control group); difference not significant at p = 0.05 level Adverse events leading to discontinuation of therapy not reported Any adverse event: treatment: 6/27 patients, including respiratory events, haemodynamic instability, rash, decreased consciousness; control: 0/16 patients
Notes	The mortality comparison includes patients who received surfactant (50 mg/kg for 8 doses and 100 mg/kg for 8 doses) versus control. We excluded the treatment arm with 100 mg/kg of phospholipids for 4 doses because it included directly (n = 8) and randomly (n = 8) allocated patients. Outcomes were not reported separately for the 8 randomized patients.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	B ‐ Unclear