{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T18:33:52Z","timestamp":1783535632103,"version":"3.55.0"},"reference-count":34,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,2,7]],"date-time":"2020-02-07T00:00:00Z","timestamp":1581033600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["LA 9-UID\/EEA\/50009\/2019"],"award-info":[{"award-number":["LA 9-UID\/EEA\/50009\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"ARDITI - Ag\u00eancia Regional para o Desenvolvimento da Investiga\u00e7\u00e3o, Tecnologia e Inova\u00e7\u00e3o","award":["M1420-09-5369-FSE-000001\u2014PhD Studentship"],"award-info":[{"award-number":["M1420-09-5369-FSE-000001\u2014PhD Studentship"]}]},{"name":"MITIExcell \u2014 EXCELENCIA INTERNACIONAL DE IDT&amp;I NAS TIC","award":["M1420-01-0145-FEDER-000002"],"award-info":[{"award-number":["M1420-01-0145-FEDER-000002"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Sleep related disorders can severely disturb the quality of sleep. Among these disorders, obstructive sleep apnea (OSA) is highly prevalent and commonly undiagnosed. Polysomnography is considered to be the gold standard exam for OSA diagnosis. Even though this multi-parametric test provides highly accurate results, it is time consuming, labor-intensive, and expensive. A non-invasive and easy to self-assemble home monitoring device was developed to address these issues. The device can perform the OSA diagnosis at the patient\u2019s home and a specialized technician is not required to supervise the process. An automatic scoring algorithm was developed to examine the blood oxygen saturation signal for a minute-by-minute OSA assessment. It was performed by analyzing statistical and frequency-based features that were fed to a classifier. Afterward, the ratio of the number of minutes classified as OSA to the time in bed in minutes was compared with a threshold for the global (subject-based) OSA diagnosis. The average accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve for the minute-by-minute assessment were, respectively, 88%, 80%, 91%, and 0.86. The subject-based accuracy was 95%. The performance is in the same range as the best state of the art methods for the models based only on the blood oxygen saturation analysis. Therefore, the developed model has the potential to be employed in clinical analysis.<\/jats:p>","DOI":"10.3390\/s20030888","type":"journal-article","created":{"date-parts":[[2020,2,7]],"date-time":"2020-02-07T11:50:28Z","timestamp":1581076228000},"page":"888","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["An Oximetry Based Wireless Device for Sleep Apnea Detection"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5107-3248","authenticated-orcid":false,"given":"F\u00e1bio","family":"Mendon\u00e7a","sequence":"first","affiliation":[{"name":"Instituto Superior T\u00e9cnico, University of Lisbon, 1049-001 Lisbon, Portugal"},{"name":"ITI\/Larsys\/Madeira Interactive Technologies Institute, 9020-105 Funchal, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7677-0971","authenticated-orcid":false,"given":"Sheikh Shanawaz","family":"Mostafa","sequence":"additional","affiliation":[{"name":"Instituto Superior T\u00e9cnico, University of Lisbon, 1049-001 Lisbon, Portugal"},{"name":"ITI\/Larsys\/Madeira Interactive Technologies Institute, 9020-105 Funchal, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7334-3993","authenticated-orcid":false,"given":"Fernando","family":"Morgado-Dias","sequence":"additional","affiliation":[{"name":"ITI\/Larsys\/Madeira Interactive Technologies Institute, 9020-105 Funchal, Portugal"},{"name":"Faculty of Exact Sciences and Engineering, University of Madeira, 9000-082 Funchal, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8512-965X","authenticated-orcid":false,"given":"Antonio G.","family":"Ravelo-Garc\u00eda","sequence":"additional","affiliation":[{"name":"ITI\/Larsys\/Madeira Interactive Technologies Institute, 9020-105 Funchal, Portugal"},{"name":"Institute for Technological Development and Innovation in Communications, Universidad de Las Palmas de Gran Canaria, 35001 Las Palmas de Gran Canaria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1279","DOI":"10.1038\/nature04287","article-title":"Insights from studying human sleep disorders","volume":"437","author":"Mahowald","year":"2005","journal-title":"Nature"},{"key":"ref_2","first-page":"11","article-title":"Why Sleep Matters-The Economic Costs of Insufficient Sleep: A Cross-Country Comparative Analysis","volume":"6","author":"Hafner","year":"2017","journal-title":"RAND Health Q."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1387","DOI":"10.1378\/chest.14-0970","article-title":"International classification of sleep disorders-third edition: Highlights and modifications","volume":"145","author":"Sateia","year":"2014","journal-title":"Chest"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1006","DOI":"10.1093\/aje\/kws342","article-title":"Increased Prevalence of Sleep-Disordered Breathing in Adults","volume":"177","author":"Peppard","year":"2013","journal-title":"Am. 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