title: A 4-compartment model based validation of air displacement plethysmography, dual energy X-ray absorptiometry, skinfold technique & bio-electrical impedance for measuring body fat in Indian adults.
abstract: OBJECTIVE
  Many methods are available for measuring body fat of an individual, each having its own advantages and limitations. The primary objective of the present study was to validate body fat estimates from individual methods using the 4-compartment (4C) model as reference. The second objective was to obtain estimates of hydration of fat free mass (FFM) using the 4C model.
  
  
  METHODS
  The body fat of 39 adults (19 men and 20 women) aged 20-40 yr was estimated using air displacement plethysmography (ADP), dual energy X-ray absorptiometry (DEXA), 4-skinfold technique and bio-electrical impedance (BIA). Total body water was estimated using isotope dilution method.
  
  
  RESULTS
  All the methods underestimated body fat when compared to 4C model, except for DEXA and the mean difference from the reference was lowest for DEXA and ADP. The precision of the fat mass estimated from 4C model using the propagation of error was 0.25 kg, while the mean hydration factor obtained by the 4C model was found to be 0.74 ± 0.02 in the whole group of men and women.
  
  
  CONCLUSIONS
  The results of the present study suggest that DEXA and ADP methods can provide reasonably accurate estimates of body fat, while skinfold and bio-electrical impedance methods require the use of population specific equations.
authors.affiliation: Division of Nutrition, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Kuriyan
authors.forename: Tinku
authors.initials: T
authors.lastname: Thomas
authors.forename: Sangeetha
authors.initials: S
authors.lastname: Ashok
authors.forename: J
authors.initials: J
authors.lastname: Jayakumar
authors.forename: Anura V
authors.initials: AV
authors.lastname: Kurpad
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000273:Adipose Tissue; D000328:Adult; D000886:Anthropometry; D001823:Body Composition; D001834:Body Water; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010991:Plethysmography / Q000379:methods; D012885:Skinfold Thickness