title: [Body composition by simple anthropometry, bioimpedance and DXA in preschool children: interrelationships among methods].
abstract: 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.
authors.affiliation: Cátedra de Bioquímica General y Bucal, Facultad de Odontología, Universidad de Buenos Aires, Argentina. patriciaguez@hotmail.com
authors.forename: Patricia N
authors.initials: PN
authors.lastname: Rodríguez
authors.forename: Enrique F
authors.initials: EF
authors.lastname: Bermúdez
authors.forename: Gabriela S
authors.initials: GS
authors.lastname: Rodríguez
authors.forename: María A
authors.initials: MA
authors.lastname: Spina
authors.forename: Susana N
authors.initials: SN
authors.lastname: Zeni
authors.forename: Silvia M
authors.initials: SM
authors.lastname: Friedman
authors.forename: Ramón A
authors.initials: RA
authors.lastname: Exeni
mesh_terms: 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