[Comparison of consistency in measurement of body fat percentage by dual-energy X-ray absorptiometry and multi-frequency bioelectrical impedance analysis in overweight and obese adults in China].

OBJECTIVE

To compare the consistency in the measurement of percentage of body fat (PBF) by multi-frequency bioelectrical impedance analysis (MF-BIA) and dual energy X-ray absorptiometry (DXA) in overweight and obese adults in China, and provide evidence for the accurate MF-BIA application in China.

METHODS

A total of 1 323 overweight/obese adults aged 22-55 years were recruited in this study. All the subjects received PBF measurement by both MF-BIA and DXA. The consistency in PBF measurement by MF-BIA and DXA was evaluated by using interclass correlation coefficients (ICC), then the correction prediction models was established.

RESULTS

The differences in PBF measurement in male subjects and female subjects between MF-BIA and DXA were statistical significant (all P < 0.01), the mean difference values were -6.5% for overweight males and -4.3% for obese males, -2.5% for overweight females and 0.5% for obese females, respectively. The difference in ICC of PBF between MF-BIA and DXA measurement were statistically significant in all subgroups (P < 0.01). The ICC was 0.746 for overweight males, 0.807 for obese males, 0.628 for overweight females and 0.674 for obese females, respectively. The correction prediction models included: PBF (DXA) = 13.425 + 0.719 × PBF (MF-BIA) for overweight males; PBF (DXA) = 12.572 + 0.741 × PBF (MF-BIA) for obese males; PBF (DXA) = 9.785 + 0.802 × PBF (MF-BIA) for overweight females; PBF (DXA) = 20.348 + 0.532 × PBF (MF-BIA) for obese females.

CONCLUSION

The consistency in PBF measurement in overweight/obese adults by MF-BIA and DXA was poor in China. Correction should be conducted when MF-BIA is used in the measurement of PBF.