{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T19:24:57Z","timestamp":1772220297346,"version":"3.50.1"},"reference-count":42,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2025,4,25]],"date-time":"2025-04-25T00:00:00Z","timestamp":1745539200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014105","name":"Federal Economic Development Agency for Southern Ontario","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100014105","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chirp"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Detecting early changes in walking speed can allow older adults to seek preventative rehabilitation. Currently, there is a lack of consensus on which assessments to use to assess walking speed and how to continuously monitor walking speed outside of the clinic. Chirp is a privacy-preserving radar sensor developed to continuously monitor older adults\u2019 safety and mobility without the need for cameras or wearable devices. Our study purpose was to evaluate the inter-sensor reliability, intrasession test-retest reliability, and concurrent validity of Chirp in a clinical setting.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We recruited 35 community-dwelling older adults (mean age 75.5 (standard deviation: 6.6) years, 86% female). All participants lived alone in an urban city in southwestern Ontario and had access to a smart device with wireless internet. Data were collected with a 4-meter ProtoKinetics Zeno\n                      <jats:sup>TM<\/jats:sup>\n                      Walkway (pressure sensors) with the Chirp sensor (radar positioning) at the end of the walkway. We assessed participants walking speed during normal and adaptive locomotion experimental conditions (walking-while-talking, obstacle, narrow walking, fast walking). We selected walking speed as a measure as it is a good predictor of functional mobility but also is associated with physical and cognitive functioning in older adults. Each of the experimental conditions was conducted twice in a randomized order, with fast walking trials performed last. For intra-session reliability testing, we conducted two blocks of walks within a participant session separated by approximately 30 minutes. Intraclass Correlation Coefficient\n                      <jats:sub>(A,1)<\/jats:sub>\n                      (ICC\n                      <jats:sub>(A,1)<\/jats:sub>\n                      ) was used to assess the reliability and validity. Linear regression, adjusted for gender, was used to investigate the association between Chirp and cognition and health-related quality of life scores.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Chirp walking speed inter-sensor reliability ICC\n                      <jats:sub>(A,1)<\/jats:sub>\n                      \u2009=\u20090.999[95% Confidence Interval [CI]: 0.997 to 0.999] and intrasession test-retest reliability [ICC\n                      <jats:sub>(A,1)<\/jats:sub>\n                      =\u20090.921, 95% CI: 0.725 to 0.969] were excellent across all experimental conditions. Chirp walking speed concurrent validity compared to the ProtoKinetics Zeno\n                      <jats:sup>TM<\/jats:sup>\n                      Walkway was excellent across experimental conditions [ICC\n                      <jats:sub>(A,1)<\/jats:sub>\n                      \u2009= 0.993, 95% CI: 0.985 to 0.997]. We found a weak association between walking speed and cognition scores using the Montreal Cognitive Assessment across experimental conditions (estimated \u03b2-value\u2009= 7.79, 95% CI: 2.79 to 12.80) and no association between walking speed and health-related quality of life using the 12-item Short Form Survey across experimental conditions (estimated \u03b2-value\u2009=\u20096.12, 95% CI: -7.12 to 19.36).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Our results demonstrate that Chirp is a reliable and valid measure to assess walking speed parameters in clinics among older adults.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0307347","type":"journal-article","created":{"date-parts":[[2025,4,25]],"date-time":"2025-04-25T13:20:42Z","timestamp":1745587242000},"page":"e0307347","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["The reliability and validity of a non-wearable indoor positioning system to assess mobility in older adults: A cross-sectional study"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3158-813X","authenticated-orcid":true,"given":"Isabel B.","family":"Rodrigues","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Patricia","family":"Hewston","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan","family":"Adachi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sayem","family":"Borhan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"George","family":"Ioannidis","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexa","family":"Kouroukis","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carolyn","family":"Leckie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrea","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-4890-4603","authenticated-orcid":true,"given":"Alexander","family":"Rabinovich","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Parthipan","family":"Siva","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rachel","family":"Swance","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Suleman","family":"Tariq","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lehana","family":"Thabane","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandra","family":"Papaioannou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2025,4,25]]},"reference":[{"key":"pone.0307347.ref001","article-title":"Global age-friendly cities: a guide","author":"World Health Organization","year":"2007"},{"issue":"9","key":"pone.0307347.ref002","doi-asserted-by":"crossref","first-page":"1634","DOI":"10.1016\/j.apmr.2015.02.033","article-title":"Mobility is a key predictor of change in well-being among older adults who experience falls: Evidence from the vancouver falls prevention clinic cohort","volume":"96","author":"JC Davis","year":"2015","journal-title":"Archives Phys Med Rehabilitation"},{"key":"pone.0307347.ref003","unstructured":"Groessl E, Kaplan R, Rejeski W, Katula J, King A, Frierson G, et al. 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