{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T20:30:41Z","timestamp":1777494641060,"version":"3.51.4"},"reference-count":59,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,11]],"date-time":"2021-01-11T00:00:00Z","timestamp":1610323200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000287","name":"Royal Academy of Engineering","doi-asserted-by":"publisher","award":["IAPP1R2\\100204"],"award-info":[{"award-number":["IAPP1R2\\100204"]}],"id":[{"id":"10.13039\/501100000287","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Introduction: Chronic Obstructive Pulmonary Disease (COPD) is a progressive disease that causes long-term breathing problems. The reliable monitoring of respiratory rate (RR) is very important for the treatment and management of COPD. Based on inkjet printing technology, we have developed a stretchable and wearable sensor that can accurately measure RR on normal subjects. Currently, there is a lack of comprehensive evaluation of stretchable sensors in the monitoring of RR on COPD patients. We aimed to investigate the measurement accuracy of our sensor on COPD patients. Methodology: Thirty-five patients (Mean \u00b1 SD of age: 55.25 \u00b1 13.76 years) in different stages of COPD were recruited. The measurement accuracy of our inkjet-printed (IJPT) sensor was evaluated at different body postures (i.e., standing, sitting at 90\u00b0, and lying at 45\u00b0) on COPD patients. The RR recorded by the IJPT sensor was compared with that recorded by the reference e-Health sensor using paired T-test and Wilcoxon signed-rank test. Analysis of variation (ANOVA) was performed to investigate if there was any significant effect of individual difference or posture on the measurement error. Statistical significance was defined as p-value less than 0.05. Results: There was no significant difference between the RR measurements collected by the IJPT sensor and the e-Health reference sensor overall and in three postures (p &gt; 0.05 in paired T-tests and Wilcoxon signed-rank tests). The sitting posture had the least measurement error of \u22120.0542 \u00b1 1.451 bpm. There was no significant effect of posture or individual difference on the measurement error or relative measurement error (p &gt; 0.05 in ANOVA). Conclusion: The IJPT sensor can accurately measure the RR of COPD patients at different body postures, which provides the possibility for reliable monitoring of RR on COPD patients.<\/jats:p>","DOI":"10.3390\/s21020468","type":"journal-article","created":{"date-parts":[[2021,1,11]],"date-time":"2021-01-11T11:36:11Z","timestamp":1610364971000},"page":"468","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Clinical Evaluation of Respiratory Rate Measurements on COPD (Male) Patients Using Wearable Inkjet-Printed Sensor"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1078-7583","authenticated-orcid":false,"given":"Ala\u2019aldeen","family":"Al-Halhouli","sequence":"first","affiliation":[{"name":"Mechatronics Engineering Department\/NanoLab, School of Applied Technical Sciences, German Jordanian University, P.O. Box 35247, Amman 11180, Jordan"},{"name":"Institute of Microtechnology, Technische Universit\u00e4t Braunschweig, 38124 Braunschweig, Germany"},{"name":"Faculty of Engineering, Middle East University, Amman 11831, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3457-3806","authenticated-orcid":false,"given":"Loiy","family":"Al-Ghussain","sequence":"additional","affiliation":[{"name":"Mechatronics Engineering Department\/NanoLab, School of Applied Technical Sciences, German Jordanian University, P.O. Box 35247, Amman 11180, Jordan"},{"name":"Mechanical Engineering Department, University of Kentucky, Lexington, KY 40506, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2011-1109","authenticated-orcid":false,"given":"Osama","family":"Khallouf","sequence":"additional","affiliation":[{"name":"Mechatronics Engineering Department\/NanoLab, School of Applied Technical Sciences, German Jordanian University, P.O. Box 35247, Amman 11180, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4174-0131","authenticated-orcid":false,"given":"Alexander","family":"Rabadi","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, University of Jordan, Amman 11942, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jafar","family":"Alawadi","sequence":"additional","affiliation":[{"name":"Mechatronics Engineering Department\/NanoLab, School of Applied Technical Sciences, German Jordanian University, P.O. Box 35247, Amman 11180, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4212-2503","authenticated-orcid":false,"given":"Haipeng","family":"Liu","sequence":"additional","affiliation":[{"name":"Research Centre for Intelligent Healthcare, Faculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9335-9167","authenticated-orcid":false,"given":"Khaled","family":"Al Oweidat","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, University of Jordan, Amman 11942, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6988-492X","authenticated-orcid":false,"given":"Fei","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8077-4548","authenticated-orcid":false,"given":"Dingchang","family":"Zheng","sequence":"additional","affiliation":[{"name":"Research Centre for Intelligent Healthcare, Faculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1095","DOI":"10.3389\/fphys.2020.01095","article-title":"Transfer Entropy Modeling of Newborn Cardiorespiratory Regulation","volume":"11","author":"Lucchini","year":"2020","journal-title":"Front. 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