Comparison of resting energy expenditure measurements by ventilated canopy and by respiration chamber

The study compared measurements of resting energy expenditure (REE) by two methods, namely the commercially available ventilated canopy (Medgraphics CCM system) and the respiration chamber. Thirty-five healthy subjects of both sexes with a wide weight range (BMI 18-33.8 kg m-2) were measured on both systems. The linear regression equation was REEcanopy = 0.66 x REEresp.cham. + 61.1 (kJ h-1), and the corresponding SEE% was 8.6%. The correlation was high (r = 0.89). However, the mean REE measured using the ventilated canopy was 41 kJ h-1 (13%) lower than that using the respiration chamber (P < 0.01). The Medgraphics CCM canopy system seems valid for measurements of REE. However, the REE results measured by the canopy were systematically lower than when measured by the respiration chamber, but can be converted by the equation given with an accuracy error of 9%.