AUTHOR=Tinsley Grant M. , Rodriguez Christian , Florez Christine M. , Siedler Madelin R. , Tinoco Ethan , McCarthy Cassidy , Heymsfield Steven B. 

TITLE=Smartphone three-dimensional imaging for body composition assessment using non-rigid avatar reconstruction

JOURNAL=Frontiers in Medicine

VOLUME=11

YEAR=2024

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2024.1485450

DOI=10.3389/fmed.2024.1485450

ISSN=2296-858X

ABSTRACT=<sec id="sec1"><title>Background</title><p>Modern digital anthropometry applications utilize smartphone cameras to rapidly construct three-dimensional humanoid avatars, quantify relevant anthropometric variables, and estimate body composition.</p></sec><sec id="sec2"><title>Methods</title><p>In the present study, 131 participants ([73 M, 58 F] age 33.7 ± 16.0 y; BMI 27.3 ± 5.9 kg/m<sup>2</sup>, body fat 29.9 ± 9.9%) had their body composition assessed using dual-energy X-ray absorptiometry (DXA) and a smartphone 3D scanning application using non-rigid avatar reconstruction. The performance of two new body fat % estimation equations was evaluated through reliability and validity statistics, Bland–Altman analysis, and equivalence testing.</p></sec><sec id="sec3"><title>Results</title><p>In the reliability analysis, the technical error of the measurement and intraclass correlation coefficient were 0.5–0.7% and 0.996–0.997, respectively. Both estimation equations demonstrated statistical equivalence with DXA based on ±2% equivalence regions and strong linear relationships (Pearson’s <italic>r</italic> 0.90; concordance correlation coefficient 0.89–0.90). Across equations, mean absolute error and standard error of the estimate values were ~ 3.5% and ~ 4.2%, respectively. No proportional bias was observed.</p></sec><sec id="sec4"><title>Conclusion</title><p>While continual advances are likely, smartphone-based 3D scanning may now be suitable for implementation for rapid and accessible body measurement in a variety of applications.</p></sec>