Research

Adherence

A heuristic algorithm (HDCZA) applied to raw wrist-worn accelerometer data can accurately estimate the Sleep Period Time window (SPT-window) without requiring a sleep diary.

To track your sleep without keeping a diary, use a wrist-worn fitness tracker that records raw acceleration data. Ensure it is worn on your non-dominant wrist continuously. The device's software (using algorithms like HDCZA) will automatically determine your sleep window based on movement and body angle, providing a reliable estimate of your sleep duration and timing without you needing to manually log your bedtime or wake time.

GoodSupportsHIGH confidence
We demonstrated the accuracy of our algorithm to detect the SPT-window. The value of this algorithm lies in studies such as UK Biobank where a sleep diary was not used.
Vincent T. van Hees et al. · Scientific Reports · 2018

Why this rating

Validated against Polysomnography (gold standard) in clinical and healthy cohorts, and against sleep diaries in a large cohort (N=3752), showing high concordance statistics (C-statistic ~0.86).

Source

Estimating sleep parameters using an accelerometer without sleep diary

Vincent T. van Hees et al. · Scientific Reports · 2018

cohort · n=3802Cited 565×
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