Research

Mixed

Consumer-grade wearable sleep-tracking devices (e.g., smartwatches, rings) provide sleep data that is comparable to or superior to traditional actigraphy when validated against polysomnography (PSG), primarily due to the integration of photoplethysmography (PPG) and machine learning algorithms.

For sleep research, modern consumer wearables (smartwatches/rings) are now more accurate than traditional actigraphy for estimating sleep stages, provided you account for their limitations in specific populations (e.g., obesity, darker skin). Do not assume 'research-grade' labels guarantee accuracy without validation; validate the specific device against PSG for your target population.

GoodSupportsHIGH confidence
the available evidence suggests that consumer-grade devices exceed the performance of traditional actigraphy in assessing sleep as defined by polysomnogram.
Massimiliano de Zambotti et al. · SLEEP · 2023

Why this rating

Based on a systematic review of performance evaluation studies, though bias toward healthy young adults is noted.

Source

State of the science and recommendations for using wearable technology in sleep and circadian research

Massimiliano de Zambotti et al. · SLEEP · 2023

DOI 10.1093/sleep/zsad325

narrative_reviewCited 198×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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