Yeh 1980.

Methods	Cross‐over design, quasi randomized, sequence of study alternated. Blinding of randomization ‐ no Blinding of intervention ‐ no Complete follow up ‐ yes Blinding of outcome measure ‐ no
Participants	10 infants BW 1200‐1820g (mean 1444+‐250g), GA 31‐34 wks (32.7+‐ 1.0 wks), AGA, 4‐15 days age. 15 sets of observations made, no details provided about multiple values on infants.
Interventions	Cross‐over design, Single vs double walled incubator. Infant own control, simultaneous measurements of IWL, VO2 under single walled incubator (Ohio Servo Care) and double walled incubator (Ohio Intensive Care). Study Period 3 hrs each condition, sequence of study condition alternated. Insensible water loss measurement using Potter bed scale.
Outcomes	Insensible water loss, oxygen consumption and carbon dioxide production under two conditions. Heat balance was calculated from oxygen consumption. Total heat loss, heat storage, heat loss, heat loss were calculated from temperatures measured. Heart rate and respiratory rate were recorded every 30 minutes.
Notes	Incubators in specific quiet area of nursery, 1m from wall farthest from the window.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Unclear risk	Cross‐over design, quasi randomized, sequence of study alternated.
Allocation concealment?	High risk	Blinding of randomization ‐ no
Blinding? All outcomes	High risk	Blinding of intervention ‐ no Blinding of outcome measure ‐ no
Incomplete outcome data addressed? All outcomes	Low risk	Complete follow up ‐ yes

Abdominal skin temperature was maintained by servocontrol at 36.5 C