[Body composition by simple anthropometry, bioimpedance and DXA in preschool children: interrelationships among methods].
OBJECTIVE
To examine the interrelationships of body composition variables derived from simple anthropometry, bioelectrical impedance (BIA) and dualenergy X-ray absorptiometry (DXA).


METHODS
A total of 230 healthy preschool children (118 males and 112 females) age 4-6 years, attending a day care center, were examined to determine body mass index (BMI) and waist circumference (WC). Percentage of body fat content (%BF) was predicted by BIA (Maltron BF- 900) and DXA (Lunar DPX-L, pediatric software).


RESULTS
BMI and WC did not show significant differences among sex, while %BF by BIA or DXA did. BIA measures were lower than DXA s (p <0.0001). Correlation between BIA vs. anthropometric methods and WC vs. DXA were moderate (Pearson r= 0.43 to 0.53), whereas the other correlations were strong (r= 0.71 to 0.83). However Bland Altman comparison showed wide limits of agreement between BIA and DXA; BIA significantly underestimated %BF as determined by DXA (p <0.0001).


CONCLUSIONS
The methods used to estimate body composition in healthy preschool children highly correlated. However, the Bland Altman procedure suggests that BIA and DXA should not be used interchangeably.
Rodríguez
Patricia N
PN
Cátedra de Bioquímica General y Bucal, Facultad de Odontología, Universidad de Buenos Aires, Argentina. patriciaguez@hotmail.com
Bermúdez
Enrique F
EF
Rodríguez
Gabriela S
GS
Spina
María A
MA
Zeni
Susana N
SN
Friedman
Silvia M
SM
Exeni
Ramón A
RA
D015502:Absorptiometry, Photon; D000886:Anthropometry; D001823:Body Composition; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male