Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation
Traditional measures of sleep or commercial wearables may not be ideal for use in operational environments. The Zulu watch is a commercial sleep-tracking device designed to collect longitudinal sleep data in real-world environments. Laboratory testing is the initial step towards validating a device...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-12-01
|
| Series: | Sensors |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1424-8220/21/1/76 |
| _version_ | 1797543593988063232 |
|---|---|
| author | Jaime K. Devine Evan D. Chinoy Rachel R. Markwald Lindsay P. Schwartz Steven R. Hursh |
| author_facet | Jaime K. Devine Evan D. Chinoy Rachel R. Markwald Lindsay P. Schwartz Steven R. Hursh |
| author_sort | Jaime K. Devine |
| collection | DOAJ |
| description | Traditional measures of sleep or commercial wearables may not be ideal for use in operational environments. The Zulu watch is a commercial sleep-tracking device designed to collect longitudinal sleep data in real-world environments. Laboratory testing is the initial step towards validating a device for real-world sleep evaluation; therefore, the Zulu watch was tested against the gold-standard polysomnography (PSG) and actigraphy. Eight healthy, young adult participants wore a Zulu watch and Actiwatch simultaneously over a 3-day laboratory PSG sleep study. The accuracy, sensitivity, and specificity of epoch-by-epoch data were tested against PSG and actigraphy. Sleep summary statistics were compared using paired samples <i>t-</i>tests, intraclass correlation coefficients, and Bland–Altman plots. Compared with either PSG or actigraphy, both the accuracy and sensitivity for Zulu watch sleep-wake determination were >90%, while the specificity was low (~26% vs. PSG, ~33% vs. actigraphy). The accuracy for sleep scoring vs. PSG was ~87% for interrupted sleep, ~52% for light sleep, and ~49% for deep sleep. The Zulu watch showed mixed results but performed well in determining total sleep time, sleep efficiency, sleep onset, and final awakening in healthy adults compared with PSG or actigraphy. The next step will be to test the Zulu watch’s ability to evaluate sleep in industrial operations. |
| first_indexed | 2024-03-10T13:46:49Z |
| format | Article |
| id | doaj.art-cacb19f083fa4dccb91b0450cb5d03ea |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-10T13:46:49Z |
| publishDate | 2020-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-cacb19f083fa4dccb91b0450cb5d03ea2023-11-21T02:31:44ZengMDPI AGSensors1424-82202020-12-012117610.3390/s21010076Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth EstimationJaime K. Devine0Evan D. Chinoy1Rachel R. Markwald2Lindsay P. Schwartz3Steven R. Hursh4Institutes for Behavior Resources, Inc., Baltimore, MD 21218, USASleep, Tactical Efficiency, and Endurance Laboratory, Warfighter Performance Department, Naval Health Research Center, San Diego, CA 92106, USASleep, Tactical Efficiency, and Endurance Laboratory, Warfighter Performance Department, Naval Health Research Center, San Diego, CA 92106, USAInstitutes for Behavior Resources, Inc., Baltimore, MD 21218, USAInstitutes for Behavior Resources, Inc., Baltimore, MD 21218, USATraditional measures of sleep or commercial wearables may not be ideal for use in operational environments. The Zulu watch is a commercial sleep-tracking device designed to collect longitudinal sleep data in real-world environments. Laboratory testing is the initial step towards validating a device for real-world sleep evaluation; therefore, the Zulu watch was tested against the gold-standard polysomnography (PSG) and actigraphy. Eight healthy, young adult participants wore a Zulu watch and Actiwatch simultaneously over a 3-day laboratory PSG sleep study. The accuracy, sensitivity, and specificity of epoch-by-epoch data were tested against PSG and actigraphy. Sleep summary statistics were compared using paired samples <i>t-</i>tests, intraclass correlation coefficients, and Bland–Altman plots. Compared with either PSG or actigraphy, both the accuracy and sensitivity for Zulu watch sleep-wake determination were >90%, while the specificity was low (~26% vs. PSG, ~33% vs. actigraphy). The accuracy for sleep scoring vs. PSG was ~87% for interrupted sleep, ~52% for light sleep, and ~49% for deep sleep. The Zulu watch showed mixed results but performed well in determining total sleep time, sleep efficiency, sleep onset, and final awakening in healthy adults compared with PSG or actigraphy. The next step will be to test the Zulu watch’s ability to evaluate sleep in industrial operations.https://www.mdpi.com/1424-8220/21/1/76actigraphysleep trackingvalidationwearable devicesleep scoringlongitudinal data collection |
| spellingShingle | Jaime K. Devine Evan D. Chinoy Rachel R. Markwald Lindsay P. Schwartz Steven R. Hursh Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation Sensors actigraphy sleep tracking validation wearable device sleep scoring longitudinal data collection |
| title | Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation |
| title_full | Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation |
| title_fullStr | Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation |
| title_full_unstemmed | Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation |
| title_short | Validation of Zulu Watch against Polysomnography and Actigraphy for On-Wrist Sleep-Wake Determination and Sleep-Depth Estimation |
| title_sort | validation of zulu watch against polysomnography and actigraphy for on wrist sleep wake determination and sleep depth estimation |
| topic | actigraphy sleep tracking validation wearable device sleep scoring longitudinal data collection |
| url | https://www.mdpi.com/1424-8220/21/1/76 |
| work_keys_str_mv | AT jaimekdevine validationofzuluwatchagainstpolysomnographyandactigraphyforonwristsleepwakedeterminationandsleepdepthestimation AT evandchinoy validationofzuluwatchagainstpolysomnographyandactigraphyforonwristsleepwakedeterminationandsleepdepthestimation AT rachelrmarkwald validationofzuluwatchagainstpolysomnographyandactigraphyforonwristsleepwakedeterminationandsleepdepthestimation AT lindsaypschwartz validationofzuluwatchagainstpolysomnographyandactigraphyforonwristsleepwakedeterminationandsleepdepthestimation AT stevenrhursh validationofzuluwatchagainstpolysomnographyandactigraphyforonwristsleepwakedeterminationandsleepdepthestimation |