Agreement of body adiposity index (BAI), bioimpedance analysis and ultrasound scanning in determining body fat

Abstract

BACKGROUND: The steadily increasing number of people with obesity requires the development of simple and accurate methodological approaches to assess the absolute and relative amount of body fat mass. The body adiposity index (BAI) is one of the indices proposed to assess the body fat percentage. However, the comparison analysis of common methods, i.e., of bio-electrical impedance analysis and ultrasound scanning, and BAI was not performed for the Russian population.AIM: Comparison analysis of the body fat percentage estimates by bio-electrical impedance analysis, ultrasound scanning, and body adiposity index in the group of adult male and females.MATERIALS AND METHODS: An examination of healthy males and females from Moscow was conducted. Height, weight, waist and hip circumferences were measured. The body fat percentage was obtained by bio-electrical impedance analysis — BIA (ABC-02 Medas), ultrasound scanning — US (BodyMetrixTM, IntelaMetrix), and body adiposity index.RESULTS: 263 females and 134 males aged 18 to 73 years participated in the study. Correlation coefficients between BAI values and the body fat percentage obtained by BIA and US were 0.749 and 0.763 (p<0.000), respectively. Comparison of body fat percentage measurements obtained by BAI, BIA and US showed the low agreement (ССС<0.90) between BAI and other methods in pooled sample as well as in the female and male groups. Comparison of the US and BAI methods revealed higher level of agreement (ССС=0.84 [0.80–0.86]) and no systematic bias. Lower level of agreement was obtained in the group of males.CONCLUSION: Conducted study allows to conclude that, at the individual level, BAI is not an appropriate method for estimating the body fat percentage relatively to other indirect methods. However, all three methods can be used in the group of pooled males and females when testing at the population level.