CircaTest Living Meta-Analysis · v1
Every peer-reviewed sleep tracker study, in one place.
CircaTest does not test devices ourselves. Every accuracy claim on this site is sourced from a published peer-reviewed validation study, and this section is the canonical store of those studies. Each entry has a permalink, full bibliographic metadata, and a structured record of the metrics it reported.
24
Studies indexed
12
PSG validations
13
Devices covered
Section 01
Recently added
All studies →The Promise of Sleep: A Multi-Sensor Approach for Accurate Sleep Stage Detection Using the Oura Ring
Altini & Kinnunen, 2021 · Sensors
The largest published Oura Ring sleep stage validation against polysomnography. The 79% four-stage agreement figure is the most-cited single accuracy number for any consumer sleep tracker and is the editorial baseline for CircaTest's Oura coverage. Authors are Oura Health employees, which is disclosed in the paper.
The role of actigraphy in the study of sleep and circadian rhythms
Ancoli-Israel et al., 2003 · Sleep
Foundational actigraphy review from the American Academy of Sleep Medicine. Establishes the ~90% accuracy figure for distinguishing sleep from wake using motion alone, which CircaTest cites in the 'how sleep trackers work' guide as the empirical floor that all consumer wearables build on.
Performance of seven consumer sleep-tracking devices compared with polysomnography
Chinoy et al., 2021 · Sleep
A 7-device same-protocol comparison from the US Naval Health Research Center. Comparable in spirit to Schyvens 2025 but earlier (2021), with different device set including Garmin Fenix 5S and Garmin Vivosmart 3. Useful editorial counterweight to Schyvens for cross-validation: the Garmin underperformance shows up in both studies.
Section 02
By device
Each device card links to its full validation history. Devices with no published validation are still listed so the gap is visible.
Oura Ring 4
rings · Current model
Oura Ring Gen 3
rings · Successor: Oura Ring 4 (2024)
Samsung Galaxy Ring
rings · Current model
Apple Watch Series 11
watches · Current model
Apple Watch Series 10
watches · Successor: Apple Watch Series 11 (2025)
Withings ScanWatch 2
watches · Current model
Garmin Venu 3
watches · Current model
Garmin Forerunner 265
watches · Current model
Polar Vantage V3
watches · Current model
Amazfit GTR 4
watches · Current model
Fitbit Charge 6
bands · Current model
Xiaomi Smart Band 9
bands · Current model
Whoop 5.0
bands · Current model
Whoop 4.0
bands · Successor: Whoop 5.0 (2025)
Fitbit Inspire 3
bands · Current model
Bellabeat Ivy
bands · Current model
Muse S Athena
headbands · Current model
Dreem 3S (Beacon Biosignals)
headbands · Successor: n/a
Withings Sleep Rx
nearables · Current model
Eight Sleep Pod 4
nearables · Current model
Empatica EmbracePlus
clinical · Current model
WatchPAT One
clinical · Current model
Section 03
By study type
- Validation studies (single device vs reference standard)
- 12
- Comparative studies (multiple devices, same protocol)
- 5
- Meta-analyses
- 4
- Methodological frameworks
- 1
- Narrative reviews
- 2
Section 04
How CircaTest evaluates studies
Our scoring rubric is public and versioned. PSG over actigraphy, larger samples over smaller, kappa over raw accuracy where both are reported, and population context over a single headline number. The methodology page explains the GRADE-style certainty heuristic CircaTest applies and the editorial inclusion criteria for the corpus.
Read the methodology →