{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T13:45:45Z","timestamp":1792503945490,"version":"4.5.0"},"reference-count":31,"publisher":"IOP Publishing","issue":"10","license":[{"start":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:00:00Z","timestamp":1792454400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:00:00Z","timestamp":1792454400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"},{"start":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:00:00Z","timestamp":1792454400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/questions\/alternative-author-rights-policies\/"},{"start":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:00:00Z","timestamp":1792454400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/questions\/alternative-author-rights-policies\/"}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Physiol. Meas."],"published-print":{"date-parts":[[2026,10,30]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    <jats:italic>Objective.<\/jats:italic>\n                    To validate the accuracy and clinical feasibility of a noncontact radar system (Sleepal AI Lamp) for assessing sleep architecture and staging. Although noncontact radar sensors can capture respiratory and motor mechanics without physical attachment, robust validation in large-scale, pathologically diverse cohorts remains scarce.\n                    <jats:italic>Approach.<\/jats:italic>\n                    Nocturnal respiratory and body movement signals were assessed in 1022 adults using simultaneous measurements from a frequency-modulated continuous-wave bedside radar and gold-standard Polysomnography. The cohort included individuals with normal sleep profiles and patients with varying severities of obstructive sleep apnea. A frequency-augmented deep learning architecture interpreted these respiratory and movement signals.\n                    <jats:italic>Main results.<\/jats:italic>\n                    In the independent validation set, binary sleep\u2013wake classification achieved 92.7% accuracy, a Cohen\u2019s kappa of 0.792, 96.4% sleep sensitivity, 80.8% sleep specificity, and a macro-averaged\n                    <jats:italic>F<\/jats:italic>\n                    1 score of 0.896. Four-stage classification (Wake, Light, Deep, and rapid eye movement (REM) sleep) achieved 77.2% accuracy, a Cohen\u2019s kappa of 0.677, a macro-averaged\n                    <jats:italic>F<\/jats:italic>\n                    1 score of 0.768, and balanced accuracy\/macro-recall of 77.4%, with stage-specific\n                    <jats:italic>F<\/jats:italic>\n                    1 scores of 0.839, 0.740, 0.691, and 0.802 for Wake, Light, Deep, and REM, respectively.\n                    <jats:italic>Significance.<\/jats:italic>\n                    The findings support the validity of the 60 GHz radar-based system for automated assessment of sleep macrostructure. By capturing stage-specific respiratory and movement phenotypes without physical attachment, this technology may provide an unobtrusive tool for home-based screening, longitudinal recovery tracking, and population-level sleep epidemiology.\n                  <\/jats:p>","DOI":"10.1088\/1361-6579\/aeb104","type":"journal-article","created":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T22:54:45Z","timestamp":1791327285000},"page":"105011","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["A contactless approach for accurate sleep stage detection using the Sleepal AI Lamp"],"prefix":"10.1088","volume":"47","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-5544-3519","authenticated-orcid":true,"given":"Zhuo","family":"Diao","sequence":"first","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yueting","family":"Li","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianpeng","family":"Wang","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shengyu","family":"Guan","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinwei","family":"Wang","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenxiong","family":"Cui","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin","family":"Shi","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tong","family":"Liu","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kailai","family":"Sun","sequence":"additional","affiliation":[{"name":"Urban Mobility Lab, Massachusetts Institute of Technology"},{"name":"Singapore-MIT Alliance for Research and Technology (SMART) Centre"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingyu","family":"Wang","sequence":"additional","affiliation":[{"name":"Shandong Medical and Pharmaceutical University Hospital"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dian","family":"Fan","sequence":"additional","affiliation":[{"name":"Hong Kong Xsmart Century Technology Co., Ltd."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4304-0112","authenticated-orcid":true,"given":"Thomas","family":"Penzel","sequence":"additional","affiliation":[{"name":"Interdisciplinary Center of Sleep Medicine, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"266","published-online":{"date-parts":[[2026,10,20]]},"reference":[{"key":"pmeaaeb104bib1","doi-asserted-by":"publisher","first-page":"212","DOI":"10.1016\/j.compbiomed.2017.08.006","type":"journal-article","article-title":"Performance comparison between wrist and chest actigraphy in combination with heart rate variability for sleep classification","volume":"89","author":"Aktaruzzaman","year":"2017","journal-title":"Comput. 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