Evaluation of bioelectrical impedance analysis in measuring body fat in 6-to-12-year-old boys compared to air displacement plethysmography

Mahaffey, Ryan; Brown, Nicola; Cramp, Mary; Morrison, Stewart C.; Drechsler, Wendy I

Abstract

Air displacement plethysmography (ADP) has been considered the 'standard' method to determine body fat in children due to superior validity and reliability compared to bioelectrical impedance analysis (BIA). However, ADP and BIA are used interchangeably despite few studies comparing measures of percentage body fat by ADP (%FMADP) with BIA (%FMBIA) in children with and without obesity. The objective of this study was to measure concurrent validity and reliability of %FMADP and %FMBIA in 6-to-12-year-old boys with and without obesity. Seventy-one boys (25 with obesity) underwent body composition assessment. Ten boys participated in intra-day reliability analysis. %FMADP was estimated by Bodpod using gender- and age-specific equations of body density. %FMBIA was estimated by a multi-frequency, hand-to-foot device using child-specific equations based on impendence. Validity was assessed by t-tests, correlation coefficients and limits of agreement (LoA); and reliability by technical error of measurement (TEM) and intraclass correlation coefficients (ICCs). Compared to %FMADP, %FMBIA was significantly underestimated in the cohort (-3.4 ± 5.6%; effect size = 0.42), and in both boys with obesity (-5.2 ± 5.5%; ES = 0.90) and without obesity (-2.4 ± 5.5%; ES = 0.52). A strong, significant positive correlation was found between %FMADP and %FMBIA (r = 0.80). Across the cohort, LoA were 22.3%, and no bias was detected. For reliability, TEM of 0.65% and 0.55%, and ICCs of 0.93 and 0.95 for %FMBIA and %FMADP respectively. Whilst both %FMADP and %FMBIA are highly reliable methods, considerable differences indicated that the devices cannot be used interchangeably in boys 6-to-12-years-old.

• Journal Article Type: Article
• Acceptance Date: Dec 8, 2022
• Online Publication Date: Dec 23, 2022
• Publication Date: Sep 28, 2023
• Deposit Date: Jan 10, 2023
• Publicly Available Date: Jun 24, 2023
• Journal: British Journal of Nutrition
• Print ISSN: 0007-1145
• Electronic ISSN: 1475-2662
• Publisher: Cambridge University Press (CUP)
• Peer Reviewed: Peer Reviewed
• Volume: 130
• Issue: 6
• Pages: 1098 - 1104
• DOI: https://doi.org/10.1017/S0007114522004019
• Keywords: Body composition, obesity, pediatric, concurrent validity, reliability
• Public URL: https://uwe-repository.worktribe.com/output/10252772
• Publisher URL: https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/evaluation-of-bioelectrical-impedance-analysis-in-measuring-body-fat-in-6to12yearold-boys-compared-to-air-displacement-plethysmography/F21354FAD7B0D4A0BAC22AE979B6263A
• Additional Information: All authors contributed to conceptualisation, study design, data analysis, data interpretation, presentation of tables and figures, writing of the manuscript and manuscript revisions. Ryan Mahaffey collected data.