Cross-validation of bioelectrical impedance analysis for the assessment of body composition in a representative sample of 6- to 13-year-old children

Abstract

Background/Objectives: (1) To cross-validate tetra-(4-BIA) and octopolar (8-BIA) bioelectrical impedance analysis vs dualenergy X-ray absorptiometry (DXA) for the assessment of total and appendicular body composition and (2) to evaluate the accuracy of external 4-BIA algorithms for the prediction of total body composition, in a representative sample of Swiss children. Subjects/Methods: A representative sample of 333 Swiss children aged 6-13 years from the Kinder-Sportstudie (KISS) (ISRCTN15360785). Whole-body fat-free mass (FFM) and appendicular lean tissue mass were measured with DXA. Body resistance (R) was measured at 50 kHz with 4-BIA and segmental body resistance at 5, 50, 250 and 500 kHz with 8-BIA. The resistance index (RI) was calculated as height 2 /R. Selection of predictors (gender, age, weight, RI4 and RI8) for BIA algorithms was performed using bootstrapped stepwise linear regression on 1000 samples. We calculated 95% confidence intervals (CI) of regression coefficients and measures of model fit using bootstrap analysis. Limits of agreement were used as measures of interchangeability of BIA with DXA. Results: 8-BIA was more accurate than 4-BIA for the assessment of FFM (root mean square error (RMSE) ¼ 0.90 (95% CI 0.82-0.98) vs 1.12 kg (1.01-1.24); limits of agreement 1.80 to -1.80 kg vs 2.24 to -2.24 kg). 8-BIA also gave accurate estimates of appendicular body composition, with RMSE p0.10 kg for arms and p0.24 kg for legs. All external 4-BIA algorithms performed poorly with substantial negative proportional bias (rX0.48, Po0.001). Conclusions: In a representative sample of young Swiss children (1) 8-BIA was superior to 4-BIA for the prediction of FFM, (2) external 4-BIA algorithms gave biased predictions of FFM and (3) 8-BIA was an accurate predictor of segmental body composition.

Relationship of physical activity with motor skills, aerobic fitness and body fat in preschool children: a cross-sectional and longitudinal study (Ballabeina)

“…Overweight and obesity were classified according to International Obesity Task Force cutoffs (Cole). As a marker of body fat we used %body fat which was measured by a four-polar single frequency bioelectric impedance (RJL Systems, Model 101A, Detroit, MI, USA) and calculated according to a validated formula reported by Kriemler et al 33 Sociocultural characteristics Sociocultural characteristics (parental migrant status and education) were assessed by questionnaire. Parental migrant status was determined by their country of birth (migrant status equals being born outside of Switzerland) 34 and educational level as the respective highest grade of school completed.…”

Validation of bioelectrical impedance analysis for total body water assessment against the deuterium dilution technique in Asian children

“…Weight was included into both TBW and FFM prediction equations, in line with another study (Kriemler et al, 2009). The rationale for the inclusion of body weight is that water is the most abundant compartment in the body, making up B65% of body weight for 8 to 10-year-old children (Fomon et al, 1982).…”

Anthropometry in cardio-metabolic risk assessment

“…Postupci analize tjelesnog sastava koji se danas provode različitim metodama temelje se na jednostavnom dvokomponentnom (razlučuju udio masne i nemasne komponente u ukupnoj tjelesnoj masi) ili pak na višekomponentnim modelima sastava tijela (1,(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24). Kvantitativna analiza tjelesnog sastava predmet je intenzivnih istraživanja od druge polovine dvadesetog stoljeća.…”

“…Proteklih dvadesetak godina opisano je niz postupaka kojima je moguće utvrditi udio pojedinih komponenata tjelesnoga sastava (1,(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24). To se odnosi ne samo na jednostavnije postupke koji se temelje na dvokomponentnom modelu tjelesnog sastava poput antropometrijskih postupaka, metoda bioelektrične impedancije, infracrvene spektrografije i hidrostatskog vaganja nego i na novije ultrazvučne i metode zračne pletizmografije.…”

“…metoda dvoenergijske rendgenske denzitometrije (DXA, od engl. dual-energy X-ray absorptiometry -apsorpciometrija pomoću X-zraka dviju različitih energija), kompjutorizirana tomografija, metoda magnetske rezonancije (14)(15)(16)(17)(18)(19).…”