{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T14:32:47Z","timestamp":1787495567171,"version":"build-2736575974"},"reference-count":48,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T00:00:00Z","timestamp":1777593600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of National Education, Republic of T\u00fcrkiye","award":["YLSY110195, 2018"],"award-info":[{"award-number":["YLSY110195, 2018"]}]},{"name":"Ministry of National Education, Republic of T\u00fcrkiye","award":["YLSY010596, 2020"],"award-info":[{"award-number":["YLSY010596, 2020"]}]},{"award":["YLSY110195, 2018"],"award-info":[{"award-number":["YLSY110195, 2018"]}],"id":[{"id":"https:\/\/ror.org\/00jga9g46","id-type":"ROR","asserted-by":"publisher"}]},{"award":["YLSY010596, 2020"],"award-info":[{"award-number":["YLSY010596, 2020"]}],"id":[{"id":"https:\/\/ror.org\/00jga9g46","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Accurate monitoring of respiratory rates is critical for early detection of a range of clinical conditions. However, standard manual counting or inadequate clinical monitoring often fails to provide reliable measurements. This study evaluated and validated the PneumoWave biosensor for respiratory rate measurement across a broad physiological range and different body postures (45\u00b0, 90\u00b0, and 180\u00b0) in both in vitro and in vivo settings. In vitro validation was performed using a SimMan ALS manikin operated at respiratory settings of 6\u201330 breaths per minute, with 10 s periods of simulated apnea. In vivo validation involved 20 healthy volunteers performing metronome-guided breathing while wearing bilateral PneumoWave biosensors. In vitro results demonstrated an excellent correlation between biosensors and manikin respiratory settings and captured all apnea events (r = 0.99, ICC = 0.99). In vivo findings showed good agreement with direct observational count (r = 0.99, R2 = 0.99, ICC = 0.99), with 97% of apnea events captured by both devices in all positions. Body postures had no significant impact on biosensor accuracy. These findings demonstrate that the PneumoWave biosensor provides accurate and reliable respiratory monitoring and supports its potential as a robust, non-invasive tool for continuous clinical and remote patient monitoring.<\/jats:p>","DOI":"10.3390\/bios16050256","type":"journal-article","created":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T06:50:01Z","timestamp":1777618201000},"page":"256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Assessment of Respiratory Rate and Simulated Apnea Utilizing the PneumoWave Biosensor: In Vitro and In Vivo Validation"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-7173-0864","authenticated-orcid":false,"given":"Burcu","family":"Kolukisa Birgec","sequence":"first","affiliation":[{"name":"Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-8917-5415","authenticated-orcid":false,"given":"Beyza","family":"Toprak","sequence":"additional","affiliation":[{"name":"Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7475-5543","authenticated-orcid":false,"given":"Alexander Balfour","family":"Mullen","sequence":"additional","affiliation":[{"name":"Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Nicol\u00f2, A., Massaroni, C., Schena, E., and Sacchetti, M. (2020). The Importance of Respiratory Rate Monitoring: From Healthcare to Sport and Exercise. Sensors, 20.","DOI":"10.3390\/s20216396"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1011","DOI":"10.1113\/expphysiol.2008.042424","article-title":"Breathing rhythms and emotions","volume":"93","author":"Homma","year":"2008","journal-title":"Exp. Physiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"8146809","DOI":"10.1155\/2016\/8146809","article-title":"Respiratory Changes in Response to Cognitive Load: A Systematic Review","volume":"2016","author":"Grassmann","year":"2016","journal-title":"Neural Plast."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"5729","DOI":"10.1113\/JP274596","article-title":"The human ventilatory response to stress: Rate or depth?","volume":"595","author":"Tipton","year":"2017","journal-title":"J. Physiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1007\/s10877-018-0222-4","article-title":"Acoustic respiration rate and pulse oximetry-derived respiration rate: A clinical comparison study","volume":"34","author":"Eisenberg","year":"2020","journal-title":"J. Clin. Monit. Comput."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"657","DOI":"10.5694\/j.1326-5377.2008.tb01825.x","article-title":"Respiratory rate: The neglected vital sign","volume":"188","author":"Cretikos","year":"2008","journal-title":"Med. J. Aust."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"832","DOI":"10.1136\/bmjqs-2017-006671","article-title":"Is everyone really breathing 20 times a minute? Assessing epidemiology and variation in recorded respiratory rate in hospitalised adults","volume":"26","author":"Badawy","year":"2017","journal-title":"BMJ Qual. Saf."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"354","DOI":"10.1007\/BF02600071","article-title":"Respiratory rate predicts cardiopulmonary arrest for internal medicine inpatients","volume":"8","author":"Fieselmann","year":"1993","journal-title":"J. Gen. Intern. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1111\/j.1365-2044.2005.04186.x","article-title":"A physiologically-based early warning score for ward patients: The association between score and outcome","volume":"60","author":"Goldhill","year":"2005","journal-title":"Anaesthesia"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.resuscitation.2006.08.020","article-title":"The objective medical emergency team activation criteria: A case-control study","volume":"73","author":"Cretikos","year":"2007","journal-title":"Resuscitation"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Massaroni, C., Nicol\u00f2, A., Schena, E., and Sacchetti, M. (2020). Remote Respiratory Monitoring in the Time of COVID-19. Front. Physiol., 11.","DOI":"10.3389\/fphys.2020.00635"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1227","DOI":"10.1080\/17476348.2023.2169138","article-title":"Rapid systematic review of respiratory rate as a vital sign of clinical deterioration in COVID-19","volume":"16","author":"Symonds","year":"2022","journal-title":"Expert Rev. Respir. Med."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1007\/s10916-022-01898-w","article-title":"Detecting Patient Deterioration Early Using Continuous Heart rate and Respiratory rate Measurements in Hospitalized COVID-19 Patients","volume":"47","author":"Peters","year":"2023","journal-title":"J. Med. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1109\/RBME.2021.3069815","article-title":"A Wearable Tele-Health System towards Monitoring COVID-19 and Chronic Diseases","volume":"15","author":"Jiang","year":"2022","journal-title":"IEEE Rev. Biomed. Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e15437","DOI":"10.2196\/15437","article-title":"An Evaluation of Agreement of Breathing Rates Measured by a Novel Device, Manual Counting, and Other Techniques Used in Clinical Practice: Protocol for the Observational VENTILATE Study","volume":"9","author":"Jones","year":"2020","journal-title":"JMIR Res. Protoc."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"48","DOI":"10.7748\/ns.21.49.48.s52","article-title":"Respiratory assessment in adults","volume":"21","author":"Moore","year":"2007","journal-title":"Nurs. Stand."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1007\/s10877-014-9621-3","article-title":"The accuracy of respiratory rate assessment by doctors in a London teaching hospital: A cross-sectional study","volume":"29","author":"Philip","year":"2015","journal-title":"J. Clin. Monit. Comput."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"570","DOI":"10.12968\/bjon.2013.22.10.570","article-title":"Staff perceptions of respiratory rate measurement in a general hospital","volume":"22","author":"Philip","year":"2013","journal-title":"Br. J. Nurs."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"van Loon, K., van Zaane, B., Bosch, E.J., Kalkman, C.J., and Peelen, L.M. (2015). Non-Invasive Continuous Respiratory Monitoring on General Hospital Wards: A Systematic Review. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0144626"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.resuscitation.2008.10.009","article-title":"The impact of introducing medical emergency team system on the documentations of vital signs","volume":"80","author":"Chen","year":"2009","journal-title":"Resuscitation"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"489","DOI":"10.12968\/bjon.2006.15.9.21087","article-title":"Why don\u2019t nurses monitor the respiratory rates of patients?","volume":"15","author":"Hogan","year":"2006","journal-title":"Br. J. Nurs."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"12821","DOI":"10.1109\/JSEN.2020.3023486","article-title":"Contactless Methods For Measuring Respiratory Rate: A Review","volume":"21","author":"Massaroni","year":"2021","journal-title":"IEEE Sens. J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"07tr01","DOI":"10.1088\/1361-6579\/ab299e","article-title":"Recent development of respiratory rate measurement technologies","volume":"40","author":"Liu","year":"2019","journal-title":"Physiol. Meas."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"e031150","DOI":"10.1136\/bmjopen-2019-031150","article-title":"Reliability of a wearable wireless patch for continuous remote monitoring of vital signs in patients recovering from major surgery: A clinical validation study from the TRaCINg trial","volume":"9","author":"Downey","year":"2019","journal-title":"BMJ Open"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e020162","DOI":"10.1136\/bmjopen-2017-020162","article-title":"Reliability of wireless monitoring using a wearable patch sensor in high-risk surgical patients at a step-down unit in the Netherlands: A clinical validation study","volume":"8","author":"Breteler","year":"2018","journal-title":"BMJ Open"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"424","DOI":"10.1097\/ALN.0000000000003029","article-title":"Vital Signs Monitoring with Wearable Sensors in High-risk Surgical Patients: A Clinical Validation Study","volume":"132","author":"Breteler","year":"2020","journal-title":"Anesthesiology"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1007\/s10877-016-9925-6","article-title":"A sneak peek into digital innovations and wearable sensors for cardiac monitoring","volume":"31","author":"Michard","year":"2017","journal-title":"J. Clin. Monit. Comput."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Canali, S., Schiaffonati, V., and Aliverti, A. (2022). Challenges and recommendations for wearable devices in digital health: Data quality, interoperability, health equity, fairness. PLoS Digit. Health, 1.","DOI":"10.1371\/journal.pdig.0000104"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Balali, P., Rabineau, J., Hossein, A., Tordeur, C., Debeir, O., and van de Borne, P. (2022). Investigating Cardiorespiratory Interaction Using Ballistocardiography and Seismocardiography\u2014A Narrative Review. Sensors, 22.","DOI":"10.3390\/s22239565"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"645","DOI":"10.1007\/s00779-010-0293-9","article-title":"Preprocessing techniques for context recognition from accelerometer data","volume":"14","author":"Figo","year":"2010","journal-title":"Pers. Ubiquitous Comput."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"035005","DOI":"10.1088\/1361-6579\/adbe23","article-title":"Accelerometer-based estimation of respiratory rate using principal component analysis and autocorrelation","volume":"46","author":"Hostrup","year":"2025","journal-title":"Physiol. Meas."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Romano, C., Schena, E., Formica, D., and Massaroni, C. (2022). Comparison between Chest-Worn Accelerometer and Gyroscope Performance for Heart Rate and Respiratory Rate Monitoring. Biosensors, 12.","DOI":"10.3390\/bios12100834"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Kolukisa Birgec, B., Langley, R., Miller, J., Meredith, O., Toprak, B., and Mullen, A.B. (2026). In Vitro Investigation of the PneumoWave Biosensor for the Identification of Central Sleep Apnea in Pediatrics. Biosensors, 16.","DOI":"10.3390\/bios16020077"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Gonzalez Utrilla, M., Henderson, B., Kelly, S., Meredith, O., Tas, B., Lawn, W., Appiah-Kusi, E., Dillon, J.F., and Strang, J. (2025). Development of Novel Wearable Biosensor for Continuous Monitoring of Central Body Motion. Appl. Sci., 15.","DOI":"10.3390\/app152011027"},{"key":"ref_35","unstructured":"Henderson, B.C. (2020). Condition Detector. (US 2020\/0129117 A1)."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Abdulsadig, R.S., Devani, N., Singh, S., Patel, Z., Pramono, R.X.A., Mandal, S., and Rodriguez-Villegas, E. (2024). Clinical Validation of Respiratory Rate Estimation Using Acoustic Signals from a Wearable Device. J. Clin. Med., 13.","DOI":"10.3390\/jcm13237199"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"e104363","DOI":"10.1136\/bmjopen-2025-104363","article-title":"Respiratory monitoring and apnoea detection in paediatric and neonatal patients using a wearable accelerometer-based chest sensor: Protocol for an observational diagnostic feasibility study","volume":"15","author":"Vennard","year":"2025","journal-title":"BMJ Open"},{"key":"ref_38","unstructured":"Troester, M., Quan, S., Berry, R., and Plante, D. (2023). The AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications, American Academy of Sleep Medicine. [3rd ed.]."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1007\/s10877-015-9697-4","article-title":"Clinical evaluation of a novel respiratory rate monitor","volume":"30","author":"Lee","year":"2016","journal-title":"J. Clin. Monit. Comput."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"e55361","DOI":"10.2196\/55361","article-title":"The Accuracy of Pulse Oxygen Saturation, Heart Rate, Blood Pressure, and Respiratory Rate Raised by a Contactless Telehealth Portal: Validation Study","volume":"8","author":"Yeh","year":"2024","journal-title":"JMIR Form. Res."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Lauteslager, T., Maslik, M., Siddiqui, F., Marfani, S., Leschziner, G.D., and Williams, A.J. (2021). Validation of a New Contactless and Continuous Respiratory Rate Monitoring Device Based on Ultra-Wideband Radar Technology. Sensors, 21.","DOI":"10.3390\/s21124027"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"055026","DOI":"10.1088\/1361-6579\/ad3c0e","article-title":"Respiratory rate monitoring in ICU patients and healthy volunteers using electrical impedance tomography: A validation study","volume":"45","author":"Wisse","year":"2024","journal-title":"Physiol. Meas."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"e36618","DOI":"10.2196\/36618","article-title":"Noncontact Longitudinal Respiratory Rate Measurements in Healthy Adults Using Radar-Based Sleep Monitor (Somnofy): Validation Study","volume":"7","author":"Toften","year":"2022","journal-title":"JMIR Biomed. Eng."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"e56027","DOI":"10.2196\/56027","article-title":"Validity of a Consumer-Based Wearable to Measure Clinical Parameters in Patients with Chronic Obstructive Pulmonary Disease and Healthy Controls: Observational Study","volume":"12","author":"Hermans","year":"2024","journal-title":"JMIR mHealth uHealth"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1089\/ped.2021.0162","article-title":"Telehealth and Remote Patient Monitoring After the COVID Pandemic","volume":"34","author":"Hegde","year":"2021","journal-title":"Pediatr. Allergy Immunol. Pulmonol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"e57367","DOI":"10.2196\/57367","article-title":"Overdose Detection Among High-Risk Opioid Users Via a Wearable Chest Sensor in a Supervised Injecting Facility: Protocol for an Observational Study","volume":"13","author":"Tas","year":"2024","journal-title":"JMIR Res. Protoc."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1164\/rccm.202107-1761OC","article-title":"Multinight Prevalence, Variability, and Diagnostic Misclassification of Obstructive Sleep Apnea","volume":"205","author":"Lechat","year":"2022","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1199","DOI":"10.5664\/jcsm.6772","article-title":"American Academy of Sleep Medicine Position Paper for the Use of a Home Sleep Apnea Test for the Diagnosis of OSA in Children","volume":"13","author":"Kirk","year":"2017","journal-title":"J. Clin. Sleep Med."}],"container-title":["Biosensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-6374\/16\/5\/256\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T19:51:02Z","timestamp":1778529062000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-6374\/16\/5\/256"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,1]]},"references-count":48,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2026,5]]}},"alternative-id":["bios16050256"],"URL":"https:\/\/doi.org\/10.3390\/bios16050256","relation":{},"ISSN":["2079-6374"],"issn-type":[{"value":"2079-6374","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,1]]}}}