{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T21:18:38Z","timestamp":1781731118174,"version":"3.54.5"},"reference-count":22,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,11]],"date-time":"2025-01-11T00:00:00Z","timestamp":1736553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Philips Innovation Hub Eindhoven"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Coughing is a symptom of many respiratory diseases. An increased amount of coughs may signal an (upcoming) health issue, while a decreasing amount of coughs may indicate an improved health status. The presence of a cough can be identified by a cough classifier. The cough density fluctuates considerably over the course of a day with a pattern that is highly subject-dependent. This paper provides a case study of cough patterns from Chronic Obstructive Pulmonary Disease (COPD) patients as determined by a stationary semi-automated cough monitor. It clearly demonstrates the variability of cough density over the observation time, its patient specificity and dependence on health status. Furthermore, an earlier established empirical finding of a linear relation between mean and standard deviation of a session\u2019s cough count is validated. An alert mechanism incorporating these findings is described.<\/jats:p>","DOI":"10.3390\/s25020404","type":"journal-article","created":{"date-parts":[[2025,1,13]],"date-time":"2025-01-13T06:42:15Z","timestamp":1736750535000},"page":"404","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Nighttime Cough Characteristics in Chronic Obstructive Pulmonary Disease Patients"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1679-7574","authenticated-orcid":false,"given":"Albertus C.","family":"den Brinker","sequence":"first","affiliation":[{"name":"Independent Researcher, 5708 DJ Helmond, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Okke","family":"Ouweltjes","sequence":"additional","affiliation":[{"name":"Philips Digital Standardization & Licensing Research, 5656 AE Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-1098-4784","authenticated-orcid":false,"given":"Ronald","family":"Rietman","sequence":"additional","affiliation":[{"name":"Philips I&S, Innovation Engineering, Data Science and AI, 5656 AE Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9057-3608","authenticated-orcid":false,"given":"Susannah","family":"Thackray-Nocera","sequence":"additional","affiliation":[{"name":"Department of Academic Respiratory Medicine, Centre for Cardiovascular and Metabolic Research, Hull York Medical School, Cottingham HU16 5JQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6876-0258","authenticated-orcid":false,"given":"Michael G.","family":"Crooks","sequence":"additional","affiliation":[{"name":"Department of Academic Respiratory Medicine, Centre for Cardiovascular and Metabolic Research, Hull York Medical School, Cottingham HU16 5JQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6135-9610","authenticated-orcid":false,"given":"Alyn H.","family":"Morice","sequence":"additional","affiliation":[{"name":"Department of Academic Respiratory Medicine, Centre for Cardiovascular and Metabolic Research, Hull York Medical School, Cottingham HU16 5JQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1609","DOI":"10.1164\/ajrccm.161.5.9908022","article-title":"Time Course and Recovery of Exacerbations in Patients with Chronic Obstructive Pulmonary Disease","volume":"161","author":"Seemungal","year":"2000","journal-title":"Am. 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