PMC

Correlation plots of estimates of change in percentage body fat (%BF) by dual-energy X-ray absorptiometry (DXA) with estimates of change in %BF by (A) air-displacement plethysmography (ADP) with use of the Siri model (P < 0.001, R² = 0.59, SEM = 0.084), (B) ADP with use of the Lohman age-specific model (P < 0.001, R² = 0.57, SEM = 0.082), (C) bioelectrical impedance analysis (BIA) with use of the Lewy et al and Suprasongsin et al equations (P < 0.001, R² = 0.44, SEM = 0.074), and (D) skinfold-thickness measurements with use of the Dezenberg et al equation (P < 0.001, R² = 0.13, SEM = 0.040).

Bland-Altman plots for magnitude bias in the estimation of change in percentage body fat (%BF) by dual-energy X-ray absorptiometry (DXA) and (A) air-displacement plethysmography (ADP) with use of the Siri equation (P < 0.01, R² = 0.12, SEM = 0.037), (B) ADP with use of the Lohman adjustment of the Siri equation (P < 0.01, R² = 0.16, SEM = 0.043), (C) bioelectrical impedance with use of the Lewy et al and Suprasongsin et al equations (P < 0.001, R² = 0.57, SEM = 0.084), and (D) skinfold-thickness measurements with use of the Dezenberg et al equation (P = NS, R² = 0.002, SEM = 0.005). The dashed lines indicate the mean differences; the shaded area represents the limits of agreement (x̄ difference ± 2 SD).

Bland-Altman plots for magnitude bias in the estimation of percentage body fat (%BF) by dual-energy X-ray absorptiometry (DXA) at baseline by (A) air-displacement plethysmography (ADP) with use of the Siri equation (P = 0.02, R² = 0.059, SEM = 0.027), (C) ADP with use of the Lohman adjustment of the Siri equation (NS, R² = 0.001, SEM = 0.003), (E) skinfold-thickness measurements with use of the Dezenberg et al equation (P < 0.001, R² = 0.38, SEM = 0.069), and (G) bioelectrical impedance analysis with use of the Lewy et al and Suprasongsin et al equations (P < 0.001, R² = 0.14, SEM = 0.041), as well as at follow-up 1 y later by (B) ADP with use of the Siri equation (NS, R² = 0.026, SEM = 0.018), (D) ADP with use of the Lohman adjustment of the Siri equation (NS, R² = 1.3 × 10⁻⁵, SEM = 0.0004), (F) skinfold thicknesses with use of the Dezenberg et al equation (P < 0.001, R² = 0.53, SEM = 0.081), and (H) bioelectrical impedance analysis with use of the Lewy et al and Suprasongsin et al equations (P < 0.01, R² = 0.082, SEM = 0.032). The dashed lines indicate the mean differences, which was significantly different from zero for panels A, E, F, G, and H (described in text); the shaded area represents the limits of agreement (x̄ difference ± 2 SD); △, subjects scanned with use of the Hologic QDR2000; ○, subjects scanned with the Hologic QDR4500A.