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Sleep TrackingEvidence & Dosage

Wearables (Oura, Whoop) and HRV-sleep correlations.

Studies last updated

Evidence at a glance

Total studies
593
With abstract
48
Meta / Systematic / RCT
163
Highly cited
50
Publication years
1997–2026

Sleep Tracking in the context of Sleep

This topic is part of our "Sleep" world. There you'll find methodology, evidence and the highest-impact levers — plus the order in which they sensibly build on each other.

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Top studies on Sleep Tracking

Ranked by influential-citation count and publication year.

  1. The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.

    Sleep Med Rev2023n=24Meta-Analysis200 influential citations

    The consumption of caffeine in response to insufficient sleep may impair the onset and maintenance of subsequent sleep. This systematic review and meta-analysis investigated the effect of caffeine on the characteristics of night-time…

  2. Prevalence of obstructive sleep apnea (OSA) among preschool aged children in the general population: A systematic review.

    Sleep Med Rev2024n=30Systematic Review191 influential citations

    Untreated pediatric obstructive sleep apnea (OSA) is associated with significant morbidities affecting behavior, neurocognitive development, endocrine and metabolic health. This systematic review evaluated prevalence of OSA reported in…

  3. Accuracy of Fitbit Charge 4, Garmin Vivosmart 4, and WHOOP Versus Polysomnography: Systematic Review.

    JMIR Mhealth Uhealth2024n=53Systematic Review179 influential citations

    <h4>Background</h4>Despite being the gold-standard method for objectively assessing sleep, polysomnography (PSG) faces several limitations as it is expensive, time-consuming, and labor-intensive; requires various equipment and technical…

  4. Sleep assessment using EEG-based wearables - A systematic review.

    Sleep Med Rev2024n=60Systematic Review131 influential citations

    Polysomnography (PSG) is the reference standard of sleep measurement, but is burdensome for the participant and labor intensive. Affordable electroencephalography (EEG)-based wearables are easy to use and are gaining popularity, yet…

  5. Effect of CPAP therapy on blood pressure in patients with obstructive sleep apnoea: a worldwide individual patient data meta-analysis.

    Eur Respir J2025n=943Meta-Analysis117 influential citations

    <h4>Background</h4>Obstructive sleep apnoea (OSA) is associated with hypertension, and OSA treatment can reduce systolic blood pressure (SBP) and diastolic blood pressure (DBP), but with a modest mean effect size and vast heterogeneity…

    Finding: CPAP treatment was associated with blood pressure reduction in patients with uncontrolled office systolic blood pressure only.

  6. Pyjamas, Polysomnography and Professional Athletes: The Role of Sleep Tracking Technology in Sport.

    202382 influential citations

    Technological advances in sleep monitoring have seen an explosion of devices used to gather important sleep metrics. These devices range from instrumented 'smart pyjamas' through to at-home polysomnography devices. Alongside these…

  7. Detection of Sleep Apnea Using Wearable AI: Systematic Review and Meta-Analysis.

    J Med Internet Res2024n=38Meta-Analysis82 influential citations

    <h4>Background</h4>Early detection of sleep apnea, the health condition where airflow either ceases or decreases episodically during sleep, is crucial to initiate timely interventions and avoid complications. Wearable artificial…

    Finding: Wearable AI achieved pooled mean accuracy, sensitivity, and specificity of 0.893, 0.793, and 0.947 for detecting apnea events in respiration.

  8. Brain stimulation techniques as novel treatment options for insomnia: A systematic review.

    J Sleep Res2023n=967systematic80 influential citations

    Despite the success of cognitive behavioural therapy for insomnia and recent advances in pharmacotherapy, many patients with insomnia do not sufficiently respond to available treatments. This systematic review aims to present the state of…

  9. The relationship between obstructive sleep apnea and asthma severity and vice versa: a systematic review and meta-analysis.

    Eur J Med Res2023n=27,912Meta-Analysis79 influential citations

    Background There is a great association between the prevalence of obstructive sleep apnea (OSA) and asthma. Nonetheless, whether OSA impacts lung function, symptoms, and control in asthma and whether asthma increases the respiratory events…

    Finding: More severe asthma or difficult-to-control asthma was independently associated with obstructive sleep apnea.

  10. Instrumental assessment of sleep bruxism: A systematic review and meta-analysis.

    Sleep Med Rev2024n=10Meta-Analysis78 influential citations

    This systematic review and meta-analysis (MA) aimed to evaluate the diagnostic validity of portable electromyography (EMG) diagnostic devices compared to the reference standard method polysomnography (PSG) in assessing sleep bruxism. This…

Frequently asked

What dosage was studied?
• Caffeine consumption (Coffee 107 mg per 250 mL; pre-workout supplement 217.5 mg) • No intervention; prevalence of obstructive sleep apnea (OSA) assessment (Not applicable) • Fitbit Charge 4, Garmin Vivosmart 4, and WHOOP wearable devices (Not applicable)
Are there safety considerations for Sleep Tracking?
• No adverse events reported in the abstract. • Not reported • Recommend screening moderate-to-severe or difficult-to-control asthma patients for OSA. • No adverse events or treatment harms were reported in the abstract.

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