Ryan P Rosendale1, Cynthia J Bartok. 1. Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania, USA. rpr135@psu.edu
Abstract
INTRODUCTION: Air-displacement plethysmography (ADP) is an age-appropriate method for measuring relative fat mass (%FM) in children; however, the accuracy of this method has not been evaluated in children aged 5 y or younger. RESULTS: Mean %FM values measured by ADP (17.9 ± 8.0%) and by total body water (TBW) (23.7 ± 6.3%) were significantly different (P < 0.001). Regression analysis of %FM by ADP vs. TBW provided a line of best fit with a slope of 0.089, r(2) = 0.013, and standard error of the estimate (SEE) = 6.3% FM (P = 0.40). DISCUSSION: The error was related to child weight and %FM, but not to behaviors (movement or vocalizations) occurring during the test sequence. A large portion of the error was attributable to imprecision in measuring small volumes. As currently designed, ADP is not an accurate method for measuring %FM in young children. Further investigation of the sources of variability will provide insight into ways of improving the accuracy of this technology for this population. METHODS: This study examined the accuracy of an ADP system modified for young children (BOD POD; Life Measurement, Concord, CA) by comparing %FM results from ADP with those obtained from TBW by deuterium (D(2)O) dilution (reference method) in 72 children aged 6-48 mo.
INTRODUCTION: Air-displacement plethysmography (ADP) is an age-appropriate method for measuring relative fat mass (%FM) in children; however, the accuracy of this method has not been evaluated in children aged 5 y or younger. RESULTS: Mean %FM values measured by ADP (17.9 ± 8.0%) and by total body water (TBW) (23.7 ± 6.3%) were significantly different (P < 0.001). Regression analysis of %FM by ADP vs. TBW provided a line of best fit with a slope of 0.089, r(2) = 0.013, and standard error of the estimate (SEE) = 6.3% FM (P = 0.40). DISCUSSION: The error was related to child weight and %FM, but not to behaviors (movement or vocalizations) occurring during the test sequence. A large portion of the error was attributable to imprecision in measuring small volumes. As currently designed, ADP is not an accurate method for measuring %FM in young children. Further investigation of the sources of variability will provide insight into ways of improving the accuracy of this technology for this population. METHODS: This study examined the accuracy of an ADP system modified for young children (BOD POD; Life Measurement, Concord, CA) by comparing %FM results from ADP with those obtained from TBW by deuterium (D(2)O) dilution (reference method) in 72 children aged 6-48 mo.
Authors: Hajar Mazahery; Pamela R von Hurst; Christopher J D McKinlay; Barbara E Cormack; Cathryn A Conlon Journal: Matern Health Neonatol Perinatol Date: 2018-06-20