childhood obesity body composition children air-displacement plethysmography
Abstract:
Body composition assessment in children provides insight into the body tissue changes associated with both normal growth and the development of childhood obesity. Most standard body composition assessment methods for adult populations are neither appropriate nor accurate for use in children. Air-displacement plethysmography (ADP) is an age-appropriate method for assessing body composition in children; however, the method has not been proven accurate in children younger than 6 years of age. This study examined the accuracy of ADP as a body composition assessment method for children 6-48 months of age by comparing relative fat mass (%FM) results from ADP versus those obtained from total body water (TBW) by deuterium dilution (reference method). Mean %FM measured by ADP (19.23% ± 9.66%) and by TBW (21.89% ± 6.32%) were significantly different (p=0.009). Regression analysis of %FM by ADP vs. TBW provided a line of best fit with a slope of 0.12, r2 = 0.04 and total error = 10.48% FM. These data suggest that ADP is currently not an accurate method for the assessment of body composition in this age cohort. Further investigation of the sources of variability will provide insight into ways of improving the accuracy of this technology for body composition assessment of young children.
