title: Hand-held indirect calorimeter offers advantages compared with prediction equations, in a group of overweight women, to determine resting energy expenditures and estimated total energy expenditures during research screening.
abstract: OBJECTIVE
  To compare standardized prediction equations to a hand-held indirect calorimeter in estimating resting energy and total energy requirements in overweight women.
  
  
  METHODS
  Resting energy expenditure (REE) was measured by hand-held indirect calorimeter and calculated by prediction equations Harris-Benedict, Mifflin-St Jeor, World Health Organization/Food and Agriculture Organization/United Nations University (WHO), and Dietary Reference Intakes (DRI). Physical activity level, assessed by questionnaire, was used to estimate total energy expenditure (TEE).
  
  
  METHODS
  Subjects (n=39) were female nonsmokers older than 25 years of age with body mass index more than 25.
  
  
  METHODS
  Repeated measures analysis of variance, Bland-Altman plot, and fitted regression line of difference. A difference within +/-10% of two methods indicated agreement.
  
  
  RESULTS
  Significant proportional bias was present between hand-held indirect calorimeter and prediction equations for REE and TEE (P<0.01); prediction equations overestimated at lower values and underestimated at higher values. Mean differences (+/-standard error) for REE and TEE between hand-held indirect calorimeter and Harris-Benedict were -5.98+/-46.7 kcal/day (P=0.90) and 21.40+/-75.7 kcal/day (P=0.78); between hand-held indirect calorimeter and Mifflin-St Jeor were 69.93+/-46.7 kcal/day (P=0.14) and 116.44+/-75.9 kcal/day (P=0.13); between hand-held indirect calorimeter and WHO were -22.03+/-48.4 kcal/day (P=0.65) and -15.8+/-77.9 kcal/day (P=0.84); and between hand-held indirect calorimeter and DRI were 39.65+/-47.4 kcal/day (P=0.41) and 56.36+/-85.5 kcal/day (P=0.51). Less than 50% of predictive equation values were within +/-10% of hand-held indirect calorimeter values, indicating poor agreement.
  
  
  CONCLUSIONS
  A significant discrepancy between predicted and measured energy expenditure was observed. Further evaluation of hand-held indirect calorimeter research screening is needed.
authors.affiliation: College of Agriculture, Biotechnology and Natural Resources, University of Nevada, Reno, 1664 N Virginia St, Mail Stop 142, Reno, NV 89557, USA. kspears@cabnr.unr.edu
authors.forename: Karen E
authors.initials: KE
authors.lastname: Spears
authors.forename: Hyunsook
authors.initials: H
authors.lastname: Kim
authors.forename: Kay M
authors.initials: KM
authors.lastname: Behall
authors.forename: Joan M
authors.initials: JM
authors.lastname: Conway
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001481:Basal Metabolism / Q000502:physiology*; D015992:Body Mass Index; D002153:Calorimetry, Indirect / Q000379:methods / Q000592:standards*; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008019:Life Style; D008433:Mathematics; D008875:Middle Aged; D018673:Nutrition Policy; D009751:Nutritional Requirements; D050177:Overweight / Q000378:metabolism*; D011237:Predictive Value of Tests; D012016:Reference Values; D012044:Regression Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014944:World Health Organization