{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T11:05:18Z","timestamp":1784891118592,"version":"3.55.0"},"reference-count":255,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,2,21]],"date-time":"2019-02-21T00:00:00Z","timestamp":1550707200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>There is an ever-growing demand for measuring respiratory variables during a variety of applications, including monitoring in clinical and occupational settings, and during sporting activities and exercise. Special attention is devoted to the monitoring of respiratory rate because it is a vital sign, which responds to a variety of stressors. There are different methods for measuring respiratory rate, which can be classed as contact-based or contactless. The present paper provides an overview of the currently available contact-based methods for measuring respiratory rate. For these methods, the sensing element (or part of the instrument containing it) is attached to the subject\u2019s body. Methods based upon the recording of respiratory airflow, sounds, air temperature, air humidity, air components, chest wall movements, and modulation of the cardiac activity are presented. Working principles, metrological characteristics, and applications in the respiratory monitoring field are presented to explore potential development and applicability for each method.<\/jats:p>","DOI":"10.3390\/s19040908","type":"journal-article","created":{"date-parts":[[2019,2,22]],"date-time":"2019-02-22T03:49:44Z","timestamp":1550807384000},"page":"908","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":385,"title":["Contact-Based Methods for Measuring Respiratory Rate"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3090-5623","authenticated-orcid":false,"given":"Carlo","family":"Massaroni","sequence":"first","affiliation":[{"name":"Unit of Measurements and Biomedical Instrumentation, Department of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4716-1667","authenticated-orcid":false,"given":"Andrea","family":"Nicol\u00f2","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, University of Rome \u201cForo Italico\u201d, 00135 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1507-231X","authenticated-orcid":false,"given":"Daniela","family":"Lo Presti","sequence":"additional","affiliation":[{"name":"Unit of Measurements and Biomedical Instrumentation, Department of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5365-5161","authenticated-orcid":false,"given":"Massimo","family":"Sacchetti","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, University of Rome \u201cForo Italico\u201d, 00135 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5863-8336","authenticated-orcid":false,"given":"Sergio","family":"Silvestri","sequence":"additional","affiliation":[{"name":"Unit of Measurements and Biomedical Instrumentation, Department of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9696-1265","authenticated-orcid":false,"given":"Emiliano","family":"Schena","sequence":"additional","affiliation":[{"name":"Unit of Measurements and Biomedical Instrumentation, Department of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6363","DOI":"10.1113\/JP275013","article-title":"Control of the depth and rate of breathing: Metabolic vs. non-metabolic inputs","volume":"595","author":"Girardi","year":"2017","journal-title":"J. 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