Assessment of adult body composition using bioelectrical impedance: comparison of researcher calculated to machine outputted values

Franco-Villoria, M., Wright, C. M. , McColl, J. , Sherriff, A. and Pearce, M. S. (2016) Assessment of adult body composition using bioelectrical impedance: comparison of researcher calculated to machine outputted values. BMJ Open, 6(1), e008922. (doi: 10.1136/bmjopen-2015-008922) (PMID:26743700) (PMCID:PMC4716172)

Abstract

Objectives: To explore the usefulness of Bioelectrical Impedance Analysis (BIA) for general use by identifying best-evidenced formulae to calculate lean and fat mass, comparing these to historical gold standard data and comparing these results with machine-generated output. In addition, we explored how to best to adjust lean and fat estimates for height and how these overlapped with body mass index (BMI). Design: Cross-sectional observational study within population representative cohort study. Setting: Urban community, North East England Participants: Sample of 506 mothers of children aged 7–8 years, mean age 36.3 years. Methods: Participants were measured at a home visit using a portable height measure and leg-to-leg BIA machine (Tanita TBF-300MA). Measures: Height, weight, bioelectrical impedance (BIA). Outcome measures: Lean and fat mass calculated using best-evidenced published formulae as well as machine-calculated lean and fat mass data. Results: Estimates of lean mass were similar to historical results using gold standard methods. When compared with the machine-generated values, there were wide limits of agreement for fat mass and a large relative bias for lean that varied with size. Lean and fat residuals adjusted for height differed little from indices of lean (or fat)/height2. Of 112 women with BMI >30 kg/m2, 100 (91%) also had high fat, but of the 16 with low BMI (<19 kg/m2) only 5 (31%) also had low fat. Conclusions: Lean and fat mass calculated from BIA using published formulae produces plausible values and demonstrate good concordance between high BMI and high fat, but these differ substantially from the machine-generated values. Bioelectrical impedance can supply a robust and useful field measure of body composition, so long as the machine-generated output is not used.

• Item Type: Articles
• Additional Information: This research was supported by a grant (G050306) from the National Prevention Research Initiative (incorporating funding from British Heart Foundation; Cancer Research UK; Department of Health; Diabetes UK; Economic and Social Research Council; Food Standards Agency; Medical Research Council; Research and Development Office for the Northern Ireland Health and Social Services; Chief Scientist Office, Scottish Government Health Directorates; Welsh Assembly Government and World Cancer Research Fund).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Franco Villoria, Dr Maria and Sherriff, Professor Andrea and Wright, Professor Charlotte and McColl, Professor John
• Authors: Franco-Villoria, M., Wright, C. M., McColl, J., Sherriff, A., and Pearce, M. S.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Dental School; College of Science and Engineering > School of Mathematics and Statistics > Statistics
• Journal Name: BMJ Open
• Publisher: BMJ Publishing Group
• ISSN: 2044-6055
• ISSN (Online): 2044-6055
• Copyright Holders: Copyright © 2016 The Authors
• First Published: First published in BMJ Open 6(1):e008922
• Publisher Policy: Reproduced under a Creative Commons License