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Stanford Sleep Study Finds Huami Smartwatch Provides Clinical-Grade Accuracy


Amazfit Arc Tracks and Detects Sleep Phases Better Than $1,000 Alternative

Huami, the second largest wearables company globally1, announced today the results of its wearable device sleep study with Stanford University Center for Sleep Sciences and Medicine, which conducts research and clinical and educational programs to improve patient care. According to the results of the study, Huami’s Amazfit Arc, a consumer wearable device, tracks sleep and wake periods with better accuracy than a commonly used clinical-grade actigraph, suggesting that Arc is a cost-effective research alternative for large-scale, clinical studies and trials.

Researchers studied minute-by-minute activity data collected from two different wearables -- Amazfit Arc and Actiwatch Spectrum by Philips -- which were worn by 31 participants over a 48-hour period. Twelve participants had no significant health issues or sleep disorders and the remaining 19 participants were patients from the Stanford University sleep clinic. Time-stamped data from each participant was recorded and compared. Researchers concluded that Arc and Actiwatch data were highly correlated, with the Arc yielding fundamentally similar sleep scoring metrics as to Actiwatch.

“Actigraphs are widely used portable wrist-worn devices that record the amount and timing of a person’s sleep and wake, but their clinical use is highly limited by their expense,” said Elaine Huo, Head of U.S. Marketing for Huami. “Until now, there was a lack of independent validation for cost-effective research alternatives. This study is the first of its kind to prove that a consumer wearable device can be used as an actigraph for sleep monitoring and that Amazfit Arc is able to produce data comparable to a research-grade actigraph.”

Additional Study Highlights

  • The auto- and low-scoring settings on the Actiwatch software (Actiware) were used to determine sleep and wake from the Actiwatch data and were used as the comparators.
  • Receiver operating characteristic curves were used to optimize the relationship between the devices.
  • Minute-by-minute Arc and Actiwatch data were highly correlated (r = 0.94, Spearman correlation) over the 48-h study period.
  • Treating the Actiwatch auto scoring as the gold standard for determination of sleep and wake, Arc has an overall accuracy of 99.0% ± 0.17% (SEM), a sensitivity of 99.4% ± 0.19%, and a specificity of 84.5% ± 1.9% for the determination of sleep.
  • As compared to the Actiwatch low scoring, Arc has an overall accuracy of 95.2% ± 0.36%, a sensitivity of 95.7% ± 0.47%, and a specificity of 91.7% ± 0.60% for the determination of sleep.

“We are pleased to provide researchers worldwide with an opportunity to advance the field of sleep study like never before and to offer consumers medical-grade data accuracy for less than $70 USD,” added Huo. “The promising results of the Stanford sleep study is another significant milestone for Huami and largely confirms what users and reviewers have been touting from the beginning -- that Amazfit offers the best low-key casual smartwatch around at a remarkable bargain, just like the Casio of the 21st century.”

For more information about the wearable device sleep study with Stanford University Center for Sleep Sciences and Medicine and Huami, visit the report: Validation of minute-to-minute scoring for sleep and wake periods in a consumer wearable device compared to an actigraphy device.

About Huami

Huami is a biometric and activity data-driven company with significant expertise in smart wearable technology. Since its inception in 2013, Huami has quickly established its global market leadership and recognition by shipping millions of smart wearable devices. In 2017, Huami shipped 18.1 Million units of smart wearable devices, more than any other company in the world, according to Frost & Sullivan. Huami owns a large biometric and activity database in the global smart wearables industry. Huami's mobile apps, Mi Fit and Amazfit, collect over ten dimensions of measurement including heart rate, electrocardiogram data, weight, body fat compositions, GPS running track, steps, sleeping duration, and more. Huami's mobile apps work hand in hand with its smart wearable devices and provide users with a comprehensive view and analysis of their data. With a wide range of data from a large number of users, Huami is well-positioned to develop new application scenarios for smart wearable technology and drive innovation. Huami has been the sole partner of Xiaomi, a leading mobile internet company and global consumer electronics brand, to design and manufacture Xiaomi-branded smart bands, watches (excluding children watches and quartz watches), scales and associated accessories, including the Mi Band series.

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1 IDC Worldwide Quarterly Wearable Device Tracker Q2/2018

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