{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T16:50:41Z","timestamp":1768409441263,"version":"3.49.0"},"reference-count":26,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2019,10,4]],"date-time":"2019-10-04T00:00:00Z","timestamp":1570147200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003958","name":"Stichting voor de Technische Wetenschappen","doi-asserted-by":"publisher","award":["NeuroSIPE Project 10739"],"award-info":[{"award-number":["NeuroSIPE Project 10739"]}],"id":[{"id":"10.13039\/501100003958","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>There is no objective gold standard to detect tremors. This concerns not only the choice of the algorithm and sensors, but methods are often designed to detect tremors in one specific group of patients during the performance of a specific task. Therefore, the aim of this study is twofold. First, an objective quantitative method to detect tremor windows (TWs) in accelerometer and electromyography recordings is introduced. Second, the tremor stability index (TSI) is determined to indicate the advantage of detecting TWs prior to analysis. Ten Parkinson\u2019s disease (PD) patients, ten essential tremor (ET) patients, and ten healthy controls (HC) performed a resting, postural and movement task. Data was split into 3-s windows, and the power spectral density was calculated for each window. The relative power around the peak frequency with respect to the power in the tremor band was used to classify the windows as either tremor or non-tremor. The method yielded a specificity of 96.45%, sensitivity of 84.84%, and accuracy of 90.80% of tremor detection. During tremors, significant differences were found between groups in all three parameters. The results suggest that the introduced method could be used to determine under which conditions and to which extent undiagnosed patients exhibit tremors.<\/jats:p>","DOI":"10.3390\/s19194301","type":"journal-article","created":{"date-parts":[[2019,10,4]],"date-time":"2019-10-04T10:54:58Z","timestamp":1570186498000},"page":"4301","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["A Power Spectral Density-Based Method to Detect Tremor and Tremor Intermittency in Movement Disorders"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9224-0284","authenticated-orcid":false,"given":"Frauke","family":"Luft","sequence":"first","affiliation":[{"name":"Department of Biomedical Signals and Systems, University of Twente, 7522 NB Enschede, The Netherlands"}]},{"given":"Sarvi","family":"Sharifi","sequence":"additional","affiliation":[{"name":"Amsterdam Neuroscience, Amsterdam UMC, Department of Neurology, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands"}]},{"given":"Winfred","family":"Mugge","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Maritime and Materials Engineering, Delft University of Technology, 2600 AA Delft, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3149-6726","authenticated-orcid":false,"given":"Alfred","family":"Schouten","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Maritime and Materials Engineering, Delft University of Technology, 2600 AA Delft, The Netherlands"},{"name":"Department of Biomechanical Engineering, University of Twente, 7522 NB Enschede, The Netherland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7483-3388","authenticated-orcid":false,"given":"Lo","family":"Bour","sequence":"additional","affiliation":[{"name":"Amsterdam Neuroscience, Amsterdam UMC, Department of Neurology, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands"}]},{"given":"Anne-Fleur","family":"van Rootselaar","sequence":"additional","affiliation":[{"name":"Amsterdam Neuroscience, Amsterdam UMC, Department of Neurology, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1796-9999","authenticated-orcid":false,"given":"Peter","family":"Veltink","sequence":"additional","affiliation":[{"name":"Department of Biomedical Signals and Systems, University of Twente, 7522 NB Enschede, The Netherlands"}]},{"given":"Tijtske","family":"Heida","sequence":"additional","affiliation":[{"name":"Department of Biomedical Signals and Systems, University of Twente, 7522 NB Enschede, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1016\/S1353-8020(08)70032-4","article-title":"Parkinsonism & related disorders. 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