title: Comparison of DXA, Siri's 2C, and Lohman' s Db-mineral models for estimating the body fat of physically active adults.
abstract: The authors used 3-component (3C) Db-mineral-model (Lohman, 1986) reference measures to cross-validate Siri's (1961) 2-component (2C) conversion formula and dual-energy X-ray absorptiometry (DXA) estimates of relative body fat (%BF) for physically active adults. Participants varied in age (18 to 59 y), body fatness, ethnicity (black, Hispanic, white), and physical activity level. The 3C Db-mineral model was used to obtain reference measures of % BF (%BF3C) for comparison with body-composition measures from DXA and hydrodensitometry. For men (n = 110) and women (n= 110), %BF3C (14.0 % BF and 24.4 % BF, respectively) was more accurately estimated by Siri's 2C formula (% FSiri; men, r = 0.97, SEE = 1.77 % BF; women, r = 0.98, SEE = 1.56 % BF) than by DXA (% FDXA; men, r = 0.86, SEE = 3.54 % BF; women, r =0.88, SEE = 3.73 % BF). The average %BFSiri (men, 15.8 % BF; women, 24.7 % BF) and % FDXA (men, 16.2 % BF; women, 26.0 %BF) differed significantly (P < 0.001) from %BF3C. Siri's 2C model estimated the average % BF3C in this sample more accurately than DXA did.
authors.affiliation: Dept of Sport and Exercise Sciences, Barry University, Miami Shores, FL 33161, USA.
authors.forename: Ann L
authors.initials: AL
authors.lastname: Gibson
authors.forename: Vivian H
authors.initials: VH
authors.lastname: Heyward
authors.forename: Christine M
authors.initials: CM
authors.lastname: Mermier
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Janot
authors.forename: M Virginia
authors.initials: MV
authors.lastname: Wilmerding
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D001823:Body Composition / Q000502:physiology*; D001826:Body Fluids / Q000378:metabolism*; D003720:Densitometry; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008903:Minerals / Q000378:metabolism*; D008962:Models, Theoretical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012737:Sex Factors
chemical_list: D008903:Minerals