title: [Estimation of body fat by DXA and the four compartment model in Mexican youth].
abstract: The objective of this study was to validate the estimation of body fat (%BF) by DXA (Dual-Energy X-Ray AbsorciomDPX-MD) against the four compartment model (4C) of body composition in 32 Mexican pubertal girls and boys (aged 9-14 y; F=16). The mean of the difference between DXA and 4C model was -3.5 %BF (p=0.171). The limits of agreement (95% = 2 SD) were +5% to -12%BF. The precision of estimated limits of y the confidence intervals were -1.9% to -5.1%BF (P = 0.050). The concordance correlation coefficient was p = 0.85. The test of accuracy for coincidence of slop intercepts between DXA and the 4C model showed no coincidence (p < 0.05). The precision by R2 explained 83% of the variance (SEE, 4.1%). The individual accuracy assess by the total error was 5.6%. The group mean accuracy by two way analysis of variance of body fat did not show interaction between method (DXA-4C model) and separate analysis of gender and overweight. However, there was an effect of method (p = 0.043) in the presence of overweight (p < 0.001). In conclusion, the estimation of percent of body fat by DXA was not precise and accurate in a group of Mexican children. However, results do not limit the utility of DXA for the measurements of body composition and its relation with health outcomes, especially in follow up studies.
authors: Centro de Investigación en Nutrición y Salud Pública, Facultad de Salud Priblica y Nutrición, Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, México.
authors: Erik
authors: E
authors: Ramírez
authors: Mauro E
authors: ME
authors: Valencia
authors: Silvia Y
authors: SY
authors: Moya Camarena
authors: Heliodoro
authors: H
authors: Alemán-Mateo
authors: Rosa O
authors: RO
authors: Méndez