
Bias

Precision

Accuracy quantified



Mean difference in kcal/day, 95% CI

Mean difference (% of gold standard EE)

SD of bias (Levene’s Ftest^{a})

Bland–Altman limits of agreement

Accuracy rates

Inaccuracy rates


    
<10 %

<15 %

>25 %

>30 %


Method
        
EE:VCO_{2}
^{b}

+141, +107 to +174

7.7 %

153

−166 to +447

61 %

79 %

2 %

0 %

EE:HB^{c}

+246

13.5 %

263

−722 to +280

31 %

52 %

13 %

5 %

−303 to −189

p < 0.001

(F 14.1)
 
p = 0.001

p < 0.001

p < 0.002

p < 0.01

p < 0.001

EE:Esp25^{d}

+156,

8.6 %

344

−531 to +843

40 %

56 %

25 %

14 %

+81 to +230

p = 0.709

(F 31.1)
 
p = 0.009

p = 0.002

p < 0.001

p < 0.001

p < 0.001

EE:Faisy^{e}

+176,

9.7 %

218

−260 to + 612

45 %

61 %

17 %

12 %

+129 to +233

p = 0.226

(F 9.0)
 
p = 0.01

p = 0.003

p < 0.001

p < 0.001

p = 0.003

EE:PSU^{f}

−22,

1.2 %

254

−529 to +458

54 %

75 %

10 %

6 %

−77 to +33

p < 0.001

(F 11.9)
 
p = 0.341

p = 0.582

p = 0.05

p = 0.023

p < 0.001

Post hoc calculation
        
EE:HB15^{g}

−10

0.5 %

257

−524 to +504

55 %

71 %

10 %

6 %

−66 to +46

p < 0.001

(F 12.3)
 
p = 0.435

p = 0.285

p = 0.05

p = 0.023

p < 0.001


EE energy expenditure, EE:Esp25 energy expenditure calculated with the European Society for Clinical Nutrition and Metabolism guideline equation of 25 kcal/kg/day, EE:Faisy energy expenditure calculated with the Faisy equation, EE:HB15 energy expenditure calculated with the Harris–Benedict equation with 15 % added, EE:PSU energy expenditure calculated with the Penn State University 2003b equation, EE:VCO
_{
2
} energy expenditure from ventilatorderived volume of carbon dioxide and nutritional respiratory quotient, HB Harris–Benedict equation
 Less than 10 % and less than 15 % accuracy rates represent the proportion of patients for which EE:VCO_{2} (or equationbased EE) predicted EE within 10 % and within 15 %, respectively, of gold standard EE:Calorimetry. Greater than 25 % and greater than 30 % inaccuracy rates represent the proportion of patients for whom EE:VCO_{2} (or equationbased EE) differed by more than 25 % and more than 30 %, respectively, from gold standard EE:Calorimetry
 All p values are relative to EE:VCO_{2}.

Ftest and p value reflect the comparison of the variance of the mean difference of EE:VCO_{2} and EE from equations. The higher the Fvalue, the higher the difference of the variances. p < 0.05 indicates that the variance of the mean difference is significantly different from EE:VCO_{2}.

^{a}Levene’s Ftest on similar variances
 Bias: ^{b} vs. ^{c}
p < 0.001; ^{b} vs. ^{d}
p = 0.709; ^{b} vs. ^{f}
p = <0.001; ^{b} vs. ^{e}
p < 0.001; ^{b} vs. ^{g}
p = 0.226; ^{c} vs. ^{d}
p < 0.001; ^{c} vs. ^{f}
p < 0.001; ^{c} vs. ^{e}
p < 0.001; ^{c} vs. ^{g}
p < 0.001; ^{d} vs. ^{f}
p = 0.001; ^{d} vs. ^{e}
p < 0.001; ^{d} vs. ^{g}
p = 0.652; ^{f} vs. ^{e}
p = 0.762; ^{e} vs. ^{g}
p < 0.001