Research
Mixed
Most commercially available consumer sleep monitors (e.g., Fitbit, Lark, Sleep Cycle) lack published validation studies comparing their sleep-wake metrics or smart-alarm features to gold-standard PSG or standard actigraphy.
Be skeptical of 'sleep quality' scores and 'smart alarms' from devices like Fitbit or Lark if they lack published validation. These devices often overestimate sleep time and misclassify stages. Use them for general trends (e.g., 'I sleep less when I drink alcohol') rather than precise medical data.
StrongRefutesHIGH confidence
There are no published validations of the accuracy of the sleep-wake metrics of the Fitbit compared to PSG or to standard actigraphy watch devices.
Why this rating
The paper explicitly states the absence of validation for these specific devices.
Source
Recent Developments in Home Sleep-Monitoring Devices
Jessica M. Kelly et al. · ISRN Neurology · 2012
narrative_reviewCited 180×
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