{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T20:36:14Z","timestamp":1771274174367,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,18]],"date-time":"2023-02-18T00:00:00Z","timestamp":1676678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Clario"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Physical activity and sleep monitoring in daily life provide vital information to track health status and physical fitness. The aim of this study was to establish concurrent validity for the new Opal Actigraphy solution in relation to the widely used ActiGraph GT9X for measuring physical activity from accelerometry epic counts (sedentary to vigorous levels) and sleep periods in daily life. Twenty participants (age 56 + 22 years) wore two wearable devices on each wrist for 7 days and nights, recording 3-D accelerations at 30 Hz. Bland\u2013Altman plots and intraclass correlation coefficients (ICCs) assessed validity (agreement) and test\u2013retest reliability between ActiGraph and Opal Actigraphy sleep durations and activity levels, as well as between the two different versions of the ActiGraph. ICCs showed excellent reliability for physical activity measures and moderate-to-excellent reliability for sleep measures between Opal versus Actigraph GT9X and between GT3X versus GT9X. Bland\u2013Altman plots and mean absolute percentage error (MAPE) also show a comparable performance (within 10%) between Opal and ActiGraph and between the two ActiGraph monitors across activity and sleep measures. In conclusion, physical activity and sleep measures using Opal Actigraphy demonstrate performance comparable to that of ActiGraph, supporting concurrent validation. Opal Actigraphy can be used to quantify activity and monitor sleep patterns in research and clinical studies.<\/jats:p>","DOI":"10.3390\/s23042296","type":"journal-article","created":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T02:29:08Z","timestamp":1676860148000},"page":"2296","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Opal Actigraphy (Activity and Sleep) Measures Compared to ActiGraph: A Validation Study"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8626-1089","authenticated-orcid":false,"given":"Vrutangkumar V.","family":"Shah","sequence":"first","affiliation":[{"name":"Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA"},{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]},{"given":"Barbara H.","family":"Brumbach","sequence":"additional","affiliation":[{"name":"OHSU-PSU School of Public Health, Oregon Health & Science University, Portland, OR 97201, USA"}]},{"given":"Sean","family":"Pearson","sequence":"additional","affiliation":[{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]},{"given":"Paul","family":"Vasilyev","sequence":"additional","affiliation":[{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]},{"given":"Edward","family":"King","sequence":"additional","affiliation":[{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5794-4155","authenticated-orcid":false,"given":"Patricia","family":"Carlson-Kuhta","sequence":"additional","affiliation":[{"name":"Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA"}]},{"given":"Martina","family":"Mancini","sequence":"additional","affiliation":[{"name":"Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7704-5459","authenticated-orcid":false,"given":"Fay B.","family":"Horak","sequence":"additional","affiliation":[{"name":"Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA"},{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]},{"given":"Kristen","family":"Sowalsky","sequence":"additional","affiliation":[{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8091-3560","authenticated-orcid":false,"given":"James","family":"McNames","sequence":"additional","affiliation":[{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"},{"name":"Department of Electrical and Computer Engineering, Portland State University, Portland, OR 97207, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2678-8823","authenticated-orcid":false,"given":"Mahmoud","family":"El-Gohary","sequence":"additional","affiliation":[{"name":"APDM Wearable Technologies-a Clario Company, Portland, OR 97201, USA"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"151","DOI":"10.2147\/NSS.S134864","article-title":"Short-and long-term health consequences of sleep disruption","volume":"2017","author":"Medic","year":"2017","journal-title":"Nat. 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