Ortolani 2000

Methods	n = 36, 2 centres Allocation concealment: not described Baseline similarity: age, APACHE II score Blinding: none Cointerventions: not clearly described Withdrawals: none Losses to follow‐up: none
Participants	Inclusions: Mechanical ventilation; bilateral CXR infiltrates, P/F less than or equal to 200 mmHg or less than or equal to 250 mmHg if PEEP at least 10 cm H2O Exclusions: duration of ARDS more than 24 hours; haemodynamic instability; severe heart or liver disease; "septic complications during trial"
Interventions	IV NAC, 50 mg/kg every 8 hours while mechanically ventilated, or IV NAC, 50 mg/kg every 8 hours and IV rutin, 5 mg/kg every 8 hours, both while mechanically ventilated, or control (250 mL of 5% dextrose in water)
Outcomes	30 day mortality (NAC and NAC plus rutin versus control): RR 0.64 (95% CI 0.32 to 1.30) Adverse events leading to discontinuation of therapy not reported Adverse effects on cardiac performance: none
Notes	Patients (n = 36) were randomized to receive NAC (n = 12), NAC and rutin (n = 12), or control (n = 12).
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	B ‐ Unclear