Evaluation of multiple frequency bio-electrical impedance analysis in paediatric subjects

The efficacy of multiple frequency bio-electrical impedance analysis (MFBIA) at discrete frequencies in predicting body cell mass, total body water, and fat-free mass compartments was investigated in healthy (n=30) and diseased (n=40) paediatric populations. Correlation coefficients achieved by comparing MFBIA with reference techniques using Deming's regression analysis were in excess of 0.9, but were not superior to those achieved comparing reference techniques with the traditional BIA application at 50 kHz. Applying the 95% limits of agreement procedure to the results showed that the agreement between the techniques was not sufficient for the technique to be of value in individual body composition assessments. The use of MFBIA at discrete frequencies does not improve the accuracy of estimations of body compartment sizes in paediatric subjects compared with those obtained with BIA at 50 kHz.