Foot-to-foot bioelectrical impedance analysis: a valuable tool for the measurement of body composition in children.
OBJECTIVE
To determine the accuracy of foot-to-foot bioelectrical impedance analysis (BIA) and anthropometric indices as measures of body composition in children.


METHODS
Comparison of foot-to-foot BIA and anthropometry to dual-energy X-ray absorptiometry (DEXA)-derived body composition in a multi-ethnic group of children.


METHODS
: Eighty-two European, NZ Maori and Pacific Island children aged 4.9-10.9 y.


METHODS
DEXA body composition, foot-to-foot bioelectrical impedance, height, weight, hip and waist measurements.


RESULTS
Using a BIA prediction equation derived from our study population we found a high correlation between DEXA and BIA in the estimation of fat-free mass (FFM), fat mass (FM) and percentage body fat (PBF) (r=0.98, 0.98 and 0.94, respectively). BIA-FFM underestimated DEXA-FFM by a mean of 0.75 kg, BIA-FM overestimated DEXA-FM by a mean of 1.02 kg and BIA-PBF overestimated DEXA-PBF by a mean of 2.53%. The correlation between six anthropometric indices (body mass index (BMI), ponderal index, Chinn's weight-for-height index, BMI standard deviation score, weight-for-length index and Cole's weight-for-height index) and DEXA were also examined. The correlation of these indices with PBF was remarkably similar (r=0.85-0.87), more variable with FM (r=0.77-0.94) and poor with FFM (r=0.41-0.75).


CONCLUSIONS
BIA correlated better than anthropometric indices in the estimation of FFM, FM and PBF. Foot-to-foot BIA is an accurate technique in the measurement of body composition.
Tyrrell
V J
VJ
Department of Pediatrics, Faculty of Medicine and Health Science, The University of Auckland, Auckland, New Zealand.
Richards
G
G
Hofman
P
P
Gillies
G F
GF
Robinson
E
E
Cutfield
W S
WS
D015502:Absorptiometry, Photon; D000886:Anthropometry; D001823:Body Composition; D002648:Child; D002675:Child, Preschool; D017097:Electric Impedance; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male