The Prevalence of Body Composition Criterion Methods for Validation Studies in Humans

Abstract

PURPOSE: To determine the recent prevalence of body composition criterion methods in validation studies of total body percent fat or fat free mass. METHODS: A literature search was performed to identify studies between 2013 - 2018 using the following key words: four component model, validation, body composition, and fat using Medline. Only human studies published in English were included. One person (L. Milliken) screened all articles and coded the results to identify the criterion and comparison methods used. For all studies where multi component models were used, a further note was made regarding what methods comprised those models. All methods were summarized to capture the prevalence of methods used in the literature for body composition validation studies. RESULTS: A total of 176 articles were identified; 128 measured total body composition or body volume articles and were included. Some studies used more than one criterion method. 10.9% of studies used a 2 component (2C) model, 67.2% used a 3C model and 10.9% used a 4C model as a criterion method. The most common 2C, 3C, and 4C models respectively were air displacement plethysmography (ADP)(9.3%), dual-energy x-ray absorptiometry (DXA) (62.5%) and ADP/DXA/total body water (TBW) (7.8%). 3.9% of studies used an inappropriate 3C or 4C model by using bioimpedance spectroscopy (BIS) in place of TBW by isotope dilution. The criterion methods used in order of prevalence were DXA (62.5%), 4C (10.9%), ADP (9.4%), isotope dilution (7.0%), magnetic resonance imaging (4.7%), 3C not including DXA (4.7%), bioelectrical impedance analysis (3.9%), and underwater weighing (1.6%). CONCLUSIONS: Body composition validation studies are dominated by DXA as a criterion method which may not be appropriate in all situations. Also, researchers are incorrectly using field methods rather than laboratory methods (most commonly using BIS for TBW) as part of the 4C model in validation studies. The gold standard for body composition validation studies remains the 4C model with TBW determined by isotope dilution.