Beyond Body Mass Index: Accurate Metabolic Disease‐Risk Phenotyping With 3D Smartphone Application

ABSTRACT Objective Smartphone applications (apps) with optical imaging capabilities are transforming the field of physical anthropometry; digital measurements of body size and shape in clinical settings are increasingly feasible. Currently available apps are usually designed around the capture of two‐dimensional images that are then transformed with app software to three‐dimensional (3D) avatars that can be used for digital anthropometry. The aim of the current study was to compare waist circumference (WC), hip circumference (HC), four other circumferences (right/left upper arm, thigh) and WC/HC evaluated with a novel high‐precision 3D smartphone app to ground‐truth measurements made with a flexible tape by a trained anthropometrist. Methods Forty‐four participants aged 20–78 years and body mass index 18.5–48.5 kg/m2 completed digital and manual circumference evaluations and dual‐energy X‐ray absorptiometry for visceral adipose tissue mass (VAT). Results 3D‐digital and ground‐truth tape WC, HC, and WC/HC estimates were highly correlated (R2s, 0.90–0.97, p