{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T01:47:07Z","timestamp":1782265627771,"version":"3.54.5"},"reference-count":55,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T00:00:00Z","timestamp":1782172800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Accurate assessment of postural sway is essential for evaluating balance disorders, rehabilitation outcomes, and fall risk. Traditional laboratory-based motion capture systems provide precise center-of-pressure (CoP) measurements, but are expensive, non-portable, and impractical for widespread clinical use. This study describes the development and testing (reliability and validity) of a portable three-dimensional (3D) camera system (Intel RealSense D415) for quantifying sway and balance. Test\u2013retest reliability was evaluated in healthy adults (n = 10; 6 males, 4 females; mean age 22.3 \u00b1 1.6 years), yielding intraclass correlation coefficients ICC = 0.84\u20130.86 (95% CI: 0.61\u20130.95). Concurrent validity, established against a laboratory-based optical motion capture system (Optotrak), demonstrated strong correlations with a mean absolute percentage error of 10.5% relative to Optotrak-derived path length measurements and high levels of agreement. Operating at 30 Hz with end-to-end latency of &lt;40 ms, the RealSense-based system provides a reliable, valid, and portable alternative to lab-based systems. Low-cost markerless motion capture systems based on standard RGB cameras have been validated for postural risk assessment, showing good consistency with gold-standard Vicon systems. These preliminary findings suggest that the system shows promise as a low-cost alternative; however, further validation in clinical populations is required before clinical deployment.<\/jats:p>","DOI":"10.3390\/s26133987","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T01:03:23Z","timestamp":1782263003000},"page":"3987","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development, Reliability, and Validity Assessment of a Portable 3D Camera-Based System for Quantifying Postural Sway and Balance"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-0241-3430","authenticated-orcid":false,"given":"Vivek Ganesh","family":"Sonar","sequence":"first","affiliation":[{"name":"Department of Computer Science & Electrical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vibhor","family":"Agrawal","sequence":"additional","affiliation":[{"name":"Department of Population Health, College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-8711-3645","authenticated-orcid":false,"given":"Krushal","family":"Kalkani","sequence":"additional","affiliation":[{"name":"Department of Population Health, College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javad","family":"Hashemi","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abhijit","family":"Pandya","sequence":"additional","affiliation":[{"name":"Department of Computer Science & Electrical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA"},{"name":"Department of Biomedical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e21046","DOI":"10.1016\/j.heliyon.2023.e21046","article-title":"Reliability of force plate-based measures of standing balance in the sub-acute stage of post-stroke recovery","volume":"9","author":"Aryan","year":"2023","journal-title":"Heliyon"},{"key":"ref_2","unstructured":"World Health Organization (2025, August 28). 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