Martin 1994.

Methods	Randomized cross‐over study comparing HME to HH.
Participants	Inclusion criteria: sedated, paralysed people requiring mechanical ventilation for > 3 days. Mean age: 64 years. Exclusion criteria: not stated. Respiratory diagnosis: 100%. Severity: not stated. Setting: ICU, France.
Interventions	HME (hygroscopic): Humid‐Vent (Gibeck). n = 11. HH: Cascade II (Bennett). n = 11. Time in study: 24 hr for each method of humidification.
Outcomes	Body temperature.
Notes	Funding: not stated.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not stated.
Allocation concealment (selection bias)	Unclear risk	Not stated.
Blinding of outcome assessment (detection bias) All outcomes	High risk	"This study was ‐ unblinded."
Incomplete outcome data (attrition bias) All outcomes	Low risk	100% follow‐up.
Selective reporting (reporting bias)	Unclear risk	No protocol available.
Other bias	Unclear risk	None identified.