{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T17:02:00Z","timestamp":1769187720448,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2019,9,28]],"date-time":"2019-09-28T00:00:00Z","timestamp":1569628800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1936586"],"award-info":[{"award-number":["1936586"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Tremor is one of the main symptoms of Parkinson\u2019s Disease (PD) that reduces the quality of life. Tremor is measured as part of the Unified Parkinson Disease Rating Scale (UPDRS) part III. However, the assessment is based on onsite physical examinations and does not fully represent the patients\u2019 tremor experience in their day-to-day life. Our objective in this paper was to develop algorithms that, combined with wearable sensors, can estimate total Parkinsonian tremor as the patients performed a variety of free body movements. We developed two methods: an ensemble model based on gradient tree boosting and a deep learning model based on long short-term memory (LSTM) networks. The developed methods were assessed on gyroscope sensor data from 24 PD subjects. Our analysis demonstrated that the method based on gradient tree boosting provided a high correlation (r = 0.96 using held-out testing and r = 0.93 using subject-based, leave-one-out cross-validation) between the estimated and clinically assessed tremor subscores in comparison to the LSTM-based method with a moderate correlation (r = 0.84 using held-out testing and r = 0.77 using subject-based, leave-one-out cross-validation). These results indicate that our approach holds great promise in providing a full spectrum of the patients\u2019 tremor from continuous monitoring of the subjects\u2019 movement in their natural environment.<\/jats:p>","DOI":"10.3390\/s19194215","type":"journal-article","created":{"date-parts":[[2019,9,30]],"date-time":"2019-09-30T05:58:33Z","timestamp":1569823113000},"page":"4215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":99,"title":["Wearable Sensors for Estimation of Parkinsonian Tremor Severity during Free Body Movements"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8588-4639","authenticated-orcid":false,"given":"Murtadha D.","family":"Hssayeni","sequence":"first","affiliation":[{"name":"Department of Computer and Electrical Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL 33431, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9772-7569","authenticated-orcid":false,"given":"Joohi","family":"Jimenez-Shahed","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA"}]},{"given":"Michelle A.","family":"Burack","sequence":"additional","affiliation":[{"name":"Department of Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0075-7663","authenticated-orcid":false,"given":"Behnaz","family":"Ghoraani","sequence":"additional","affiliation":[{"name":"Department of Computer and Electrical Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL 33431, USA"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"756","DOI":"10.1136\/pgmj.2005.032979","article-title":"Differential diagnosis of common tremor syndromes","volume":"81","author":"Bhidayasiri","year":"2005","journal-title":"Postgrad. 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