Purpose: Whether the evaluation of body composition in obese people using low-cost, simple bedside, two-compartment techniques reflects the data obtained by indirect methods such as dual x-ray absorptiometry (DEXA) remains controversial. The aim of this study was to compare the data obtained by three methods of assessment of body composition (DEXA; bioelectrical impedance, BIA; and near infrared interactance, NII).
Method: Data on body composition obtained in 53 obese women by these three methods were compared, using the Bland and Altman procedure to test the relative validity.
Results: Although the correlation coefficients between DEXA and the two other methods were high, there were some major differences (limits of agreement) between data concerning fat and lean mass.
Conclusions: The present study indicates that these methods cannot be considered as interchangeable and raises some questions on the use of BIA and NII as a single method of evaluation of body composition in clinical research and practice in obese populations.