Agreement between anthropometric equations and air displacement plethysmography for predicting body fat in people with overweight or obesity

Abstract

The aim of this study was to compare different anthropometric equations for estimating percentage body fat (%BF) in overweight and obese individuals, using air displacement plethysmography (ADP). A total of 451 participants were selected (women: n=357, age 41.4 ± 8.91 years, BMI 34.0 ± 2.52 kg/m²; men: n=94, age 42.1 ± 11.3 years, BMI 35.4 ± 2.26 kg/m²). The %BF was verified by ADP and by the equations of Tran & Weltman, Visser et al., Deurenberg et al., Lean et al., Gallagher et al., and Gómez-Ambrosi et al. Normality was assessed using the Shapiro-Wilk test. Pearson's correlation coefficient (r) evaluated the relationship between body composition methods, and Bland-Altman analysis assessed result agreement. For overweight men, the Deurenberg et al. equation showed no significant difference (p=0.186) compared to ADP, with a strong correlation (r=0.98) and a mean error of -2.6 (95%CI -16.1; 10.9). In women, agreement was found only for the Lean et al. equation for both overweight (P=0.916) and obese (P=0.747) groups. Other equations lacked agreement with ADP (P>0.05). The Deurenberg et al. equation is recommended for overweight men, while the Lean et al. equation is suggested for overweight and obese women. New anthropometric equations for assessing %BF in obese men is needed.