Tramontini 2007.

Methods	Single centre quasi‐RCT, Brazil
Participants	81 patients over age 60 undergoing elective surgery with a surgical duration of at least one hour. Average age approximately 68 years. 42 women and 39 men
Interventions	1) Routine care with no particular attention paid to warming 2) Entire body (including head) covered with an acrylic woollen blanket 3) Dorsal region only covered with blanket
Outcomes	Temperature at induction, after 15 minutes, 30 minutes and 1 hour
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	'probabilistic sample technique ..first drawn name was part of experimental group 1, second experimental group 2 and third the control group'
Allocation concealment (selection bias)	High risk	'surgical room already prepared according to the study group which the patient was designated'
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported
Blinding of outcome assessment (detection bias) Other outcomes	Unclear risk	None reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	None lost to follow up
Selective reporting (reporting bias)	Unclear risk	No clear evidence
Other bias	Low risk	None expected