Resumen de Comparison of fat mass and fat-free mass between Anthropometry, BIA and DEXA in young females: are methods really interchangeable?

Francisco Alburquerque Sendín, Francisco Javier Martín Vallejo , Paloma García-Talavera San Miguel, Teresa Martín Gómez, Miguel Santos del Rey

• The aim of this study was to check the degree of consistency and agreement between three methods for the estimation of body composition, fat mass and fat-free mass after their application to a group of young women. A transverse observation study was performed. Fifty-nine women aged between 18 and 28 years old were included. Each woman was subjected to three assessments of body composition: anthropometry, dual-energy x-ray absorptiometry and bio-impedance analysis. Pearson’s r coefficient and the Cronbach α were calculated. To check the degree of agreement, analysis of variance was implemented for repeated measurements and Bland and Altman plot was used. Differences were observed among the four assessment methodologies, the results of the General Durnin & Womersley Formula departing from those of the others, such that it was left out. In contrast, the consistency of the Specific Durnin & Womersley Formula was better in fat mass. Regarding the level of agreement between pairs of methods, a homogenous pattern was observed, with low bias, although broad 95% agreement limits were observed. These results indicate that different methods of body composition assessment provide different estimations in a sample of healthy young women. Dual-energy x-ray absorptiometry and anthropometry (Specific Durnin & Womersley Formula) have high levels of consistency, with low bias ranges.