{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T22:35:29Z","timestamp":1773786929291,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,9]],"date-time":"2023-05-09T00:00:00Z","timestamp":1683590400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Donald E. Bentley Center for Engineering Innovation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Balance assessment, or posturography, tracks and prevents health complications for a variety of groups with balance impairment, including the elderly population and patients with traumatic brain injury. Wearables can revolutionize state-of-the-art posturography methods, which have recently shifted focus to clinical validation of strictly positioned inertial measurement units (IMUs) as replacements for force-plate systems. Yet, modern anatomical calibration (i.e., sensor-to-segment alignment) methods have not been utilized in inertial-based posturography studies. Functional calibration methods can replace the need for strict placement of inertial measurement units, which may be tedious or confusing for certain users. In this study, balance-related metrics from a smartwatch IMU were tested against a strictly placed IMU after using a functional calibration method. The smartwatch and strictly placed IMUs were strongly correlated in clinically relevant posturography scores (r = 0.861\u20130.970, p &lt; 0.001). Additionally, the smartwatch was able to detect significant variance (p &lt; 0.001) between pose-type scores from the mediolateral (ML) acceleration data and anterior-posterior (AP) rotation data. With this calibration method, a large problem with inertial-based posturography has been addressed, and wearable, \u201cat-home\u201d balance-assessment technology is within possibility.<\/jats:p>","DOI":"10.3390\/s23104585","type":"journal-article","created":{"date-parts":[[2023,5,10]],"date-time":"2023-05-10T01:57:51Z","timestamp":1683683871000},"page":"4585","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Balance Assessment Using a Smartwatch Inertial Measurement Unit with Principal Component Analysis for Anatomical Calibration"],"prefix":"10.3390","volume":"23","author":[{"given":"Benjamin M.","family":"Presley","sequence":"first","affiliation":[{"name":"Mechanical Engineering, College of Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeffrey C.","family":"Sklar","sequence":"additional","affiliation":[{"name":"Statistics, College of Science and Mathematics, California Polytechnic State University, San Luis Obispo, CA 93407, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Scott J.","family":"Hazelwood","sequence":"additional","affiliation":[{"name":"Mechanical Engineering, College of Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA"},{"name":"Biomedical Engineering, College of Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-3595-6996","authenticated-orcid":false,"given":"Britta","family":"Berg-Johansen","sequence":"additional","affiliation":[{"name":"Biomedical Engineering, College of Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2459-2664","authenticated-orcid":false,"given":"Stephen M.","family":"Klisch","sequence":"additional","affiliation":[{"name":"Mechanical Engineering, College of Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA"},{"name":"Biomedical Engineering, College of Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Greene, B.R., McManus, K., Ader, L.G.M., and Caulfield, B. 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