Xi 2010.

Methods	Prospective, multi‐centre RCT
Participants	n = 110 Inclusion criteria ARDS (PaO2 ≤ 200 mmHg at FiO2 1.0 and PEEP ≥ 10 cm H2O) Absence of left atrial hypertension or PCWP ≤ 18 mmHg Age > 18 years, stable haemodynamics Exclusion criteria Acute myocardial infarction within preceding week Preexisting chronic respiratory insufficiency Anatomical chest well abnormalities Chest tube with persistent air leak, pneumothorax or bronchopleural fistula Gross barotrauma in any form Pregnancy Malignant disease or end‐stage chronic disease Anatomical lobectomy within 2 weeks Bone marrow transplantation or lung transplantation Chronic liver disease Intracranial pressure or neuromuscular disease that could impair spontaneous breathing Previous inclusion in this study or participation in another study
Interventions	Treatment: RM (CPAP 40 cm H2O for 40 seconds) performed 8‐hourly for first 5 days, unless weaning standard was reached Both groups: VT 6‐8 mL/kg; Pplat < 30 cmH2O; VCV or PCV for first 24 hours, with any mode thereafter; PEEP titrated to target PaO2 or FiO2 or both; permissive hypercapnia
Outcomes	Primary: ICU mortality Secondary: number of ventilator‐free days; non‐pulmonary organ dysfunction‐free days from day 1 to day 28; 28‐day mortality; percentage of unassisted breathing hours for at least 48 consecutive hours; incidence of barotrauma or pneumatocoele > 2 cm
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated random numbers
Allocation concealment (selection bias)	Low risk	Sealed envelopes
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not stated
Incomplete outcome data (attrition bias) All outcomes	Low risk	15 participants were excluded for failure to follow the study protocol.
Selective reporting (reporting bias)	Unclear risk	15 participants were excluded for failure to follow the study protocol ‐ 3 in the control group and 12 in the intervention group (not analysed as intention‐to‐ treat).
Intention to treat	High risk	15 participants were excluded from final analysis for failure to adhere to study protocol.