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While traditional methods already measure these parameters with high accuracy, they still require contact-based sensors, limiting their practicality for continuous monitoring. This study evaluates radar as a non-contact alternative by validating multiple radar-derived respiratory metrics against impedance pneumography measurements in 30 healthy volunteers at rest. Synchronous recordings from both modalities were analysed to assess agreement across methods using descriptive statistics, scatter plots, modified Bland-Altman plots, and equivalence testing (TI: \u00b10.3\u00a0s, TE: \u00b10.3\u00a0s, RR: \u00b12 brpm, I:E ratio: \u00b10.2). Equivalence testing indicated high correlation (\n                    <jats:italic>p<\/jats:italic>\n                    \u2009\u2264\u20090.001***) across all metrics, with 81.8% (TI), 77.6% (TE), 97.2% (RR), and 85.7% (I:E ratio) of values within predefined bounds. These findings highlight radar\u2019s potential for continuous respiratory monitoring, particularly in medical fields where minimizing patient burden is essential as in palliative, post anaesthesia, and intensive care settings.\n                  <\/jats:p>","DOI":"10.1038\/s41598-026-42517-9","type":"journal-article","created":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T07:35:00Z","timestamp":1772609700000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Radar-based inspiratory-to-expiratory time ratio estimation: a validation study"],"prefix":"10.1038","volume":"16","author":[{"given":"Thanh Tr\u00fac","family":"Tr\u1ea7n","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marie","family":"Oesten","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefan G.","family":"Griesshammer","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anke","family":"Malessa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kilin","family":"Shi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Heckel","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bjoern M.","family":"Eskofier","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexander","family":"Koelpin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christoph","family":"Ostgathe","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tobias","family":"Steigleder","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,3,4]]},"reference":[{"key":"42517_CR1","doi-asserted-by":"crossref","unstructured":"Silbernagl, S. & Despopoulos, A. 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