Tinsley GM, et al. - Researchers assessed four commercially available 3-dimensional optical (3DO) scanners (FIT3D, Naked Labs, Size Stream, and Styku) concerning their precision in providing body composition estimates. Further, they evaluated their validity as compared with a reference 4-component (4C) model. Assessment of the body composition was done in 171 participants using four commercially-available 3DO scanners as wells as using a 4C model utilizing data from dual-energy x-ray absorptiometry, air displacement plethysmography, and bioimpedance spectroscopy. Relatively reliable body composition estimates were produced with the commercially available 3DO scanners. Three out of four scanners exhibited equivalence with a 4C model for evaluations of body fat percentage, fat mass, and fat-free mass, although there was variation in other metrics of validity among scanners and there was a proportional bias for all scanners.