{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T20:15:07Z","timestamp":1771359307152,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,5,4]],"date-time":"2019-05-04T00:00:00Z","timestamp":1556928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006054","name":"Universidad de Guanajuato","doi-asserted-by":"publisher","award":["SN"],"award-info":[{"award-number":["SN"]}],"id":[{"id":"10.13039\/501100006054","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Universidad Aut\u00f3noma Benito Ju\u00e1rez de Oaxaca","award":["SN"],"award-info":[{"award-number":["SN"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Early detection of different levels of tremors helps to obtain a more accurate diagnosis of Parkinson\u2019s disease and to increase the therapy options for a better quality of life for patients. This work proposes a non-invasive strategy to measure the severity of tremors with the aim of diagnosing one of the first three levels of Parkinson\u2019s disease by the Unified Parkinson\u2019s Disease Rating Scale (UPDRS). A tremor being an involuntary motion that mainly appears in the hands; the dataset is acquired using a leap motion controller that measures 3D coordinates of each finger and the palmar region. Texture features are computed using sum and difference of histograms (SDH) to characterize the dataset, varying the window size; however, only the most fundamental elements are used in the classification stage. A machine learning classifier provides the final classification results of the tremor level. The effectiveness of our approach is obtained by a set of performance metrics, which are also used to show a comparison between different proposed designs.<\/jats:p>","DOI":"10.3390\/s19092072","type":"journal-article","created":{"date-parts":[[2019,5,9]],"date-time":"2019-05-09T11:22:35Z","timestamp":1557400955000},"page":"2072","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Contrast and Homogeneity Feature Analysis for Classifying Tremor Levels in Parkinson\u2019s Disease Patients"],"prefix":"10.3390","volume":"19","author":[{"given":"Guillermina","family":"Vivar","sequence":"first","affiliation":[{"name":"Department of Electronics Engineering, Universidad de Guanajuato, Salamanca Gto. C.P. 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3373-0929","authenticated-orcid":false,"given":"Dora-Luz","family":"Almanza-Ojeda","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Universidad de Guanajuato, Salamanca Gto. C.P. 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Irene","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Computing Science, University of Alberta, Edmonton, AB T6G 2E9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0862-7612","authenticated-orcid":false,"given":"Juan Carlos","family":"Gomez","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Universidad de Guanajuato, Salamanca Gto. C.P. 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1362-2231","authenticated-orcid":false,"given":"J. A.","family":"Andrade-Lucio","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Universidad de Guanajuato, Salamanca Gto. C.P. 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4317-0248","authenticated-orcid":false,"given":"Mario-Alberto","family":"Ibarra-Manzano","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Universidad de Guanajuato, Salamanca Gto. C.P. 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1356","DOI":"10.1056\/NEJM2003ra020003","article-title":"\u201cAlzheimer\u2019s Disease and Parkinson\u2019s Disease\u201d","volume":"348","author":"Nussbaum","year":"2003","journal-title":"N. Engl. J. 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