Proposal of new body composition prediction equations from bioelectrical impedance for Indonesian men

BACKGROUND/OBJECTIVES: Bioelectrical impedance analysis (BIA) is one of the most affordable and feasible body composition assessment techniques for clinical and field settings. However, it is important to use an equation appropriate for the study population. This study aimed to propose and validate prediction equations to estimate body composition using BIA for Indonesian men.

SUBJECTS/METHODS: Total body water (TBW), fat-free mass (FFM) and fat mass (FM) were determined using the deuterium dilution technique in 292 Indonesian males. Participants were divided equally into development and validation groups to develop prediction equations and to cross-validate the proposed prediction equations, respectively. In addition, selected prediction equations using BIA were cross-validated.

RESULTS: The proposed BIA equations were valid in our cross-validation samples. The best performance equations obtained from the absolute measure of body composition (TBW, FFM and FM) showed that r ranged between 0.89 and 0.91 and standard error of the estimate=1.8-2.6 kg. Cross-validation analysis indicated that the proposed equations had a bias of 0.1-0.3 kg, pure error of 1.3-1.8 kg and limits of agreement (mean difference±1.96 s.d.) of -0.26 to 0.13±4.09 to 5.59 kg. Among existing prediction equations examined, those by Deurenberg et al. (1989) and Lukaski et al. (1987) significantly overestimated FM by 4.0 and 3.2 kg, respectively, whereas the equation by Deurenberg et al. (1991) significantly (P<0.001) underestimated FFM by 5.0 kg compared with the reference FFM.

CONCLUSIONS: The new BIA prediction equations may provide more precise and accurate estimation of body composition in Indonesian men than the existing equations.