title: Air-displacement plethysmography pediatric option in 2-6 years old using the four-compartment model as a criterion method.
abstract: The objective of this study was to determine the accuracy, precision, bias, and reliability of percent fat (%fat) determined by air-displacement plethysmography (ADP) with the pediatric option against the four-compartment model in 31 children (4.1 ± 1.2 years, 103.3 ± 10.2 cm, 17.5 ± 3.4 kg). %Fat was determined by (BOD POD Body Composition System; COSMED USA, Concord, CA) with the pediatric option. Total body water (TBW) was determined by isotope dilution ((2)H(2)O; 0.2 g/kg) while bone mineral was determined by dual-energy X-ray absorptiometry (DXA) (Lunar iDXA v13.31; GE, Fairfield, CT and analyzed using enCore 2010 software). The four-compartment model by Lohman was used as the criterion measure of %fat. The regression for %fat by ADP vs. %fat by the four-compartment model did not deviate from the line of identity where: y = 0.849(x) + 4.291. ADP explained 75.2% of the variance in %fat by the four-compartment model while the standard error of the estimate (SEE) was 2.09 %fat. The Bland-Altman analysis showed %fat by ADP did not exhibit any bias across the range of fatness (r = 0.04; P = 0.81). The reliability of ADP was assessed by the coefficient of variation (CV), within-subject SD, and Cronbach's α. The CV was 3.5%, within-subject SD was 0.9%, and Cronbach's α was 0.95. In conclusion, ADP with the pediatric option is accurate, precise, reliable, and without bias in estimating %fat in children 2-6 years old.
authors.affiliation: Department of Pediatrics, Section of Endocrinology and Diabetes, and Children's Hospital Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA. dfields@ouhsc.edu
authors.forename: David A
authors.initials: DA
authors.lastname: Fields
authors.forename: David B
authors.initials: DB
authors.lastname: Allison
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000388:Air; D000886:Anthropometry / Q000379:methods*; D015982:Bias; D001823:Body Composition; D001834:Body Water; D015519:Bone Density; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007201:Indicator Dilution Techniques; D007554:Isotopes; D008297:Male; D008954:Models, Biological; D010991:Plethysmography / Q000379:methods*; D015203:Reproducibility of Results; D012984:Software
chemical_list: D007554:Isotopes