Assessing the performance of a commercial multisensory sleep tracker

Abstract

Wearable sleep technology allows for a less intruding sleep assessment than PSG, especially in long-term sleep monitoring. Though such devices are less accurate than PSG, sleep trackers may still provide valuable information. This study aimed to validate a commercial sleep tracker, Garmin Vivosmart 4 (GV4), against polysomnography (PSG) and to evaluate intra-device reliability (GV4 vs. GV4). Eighteen able-bodied adults (13 females, M = 56.1 ± 12.0 years) with no self-reported sleep disorders were simultaneously sleep monitored by GV4 and PSG for one night while intra-device reliability was monitored in one participant for 23 consecutive nights. Intra-device agreement was considered sufficient (observed agreement = 0.85 ± 0.13, Cohen’s kappa = 0.68 ± 0.24). GV4 detected sleep with high accuracy (0.90) and sensitivity (0.98) but low specificity (0.28). Cohen’s kappa was calculated for sleep/wake detection (0.33) and sleep stage detection (0.20). GV4 significantly underestimated time awake (p = 0.001) including wake after sleep onset (WASO) (p = 0.001), and overestimated light sleep (p = 0.045) and total sleep time (TST) (p = 0.001) (paired t-test). Sleep onset and sleep end differed insignificantly from PSG values. Our results suggest that GV4 is not able to reliably describe sleep architecture but may allow for detection of changes in sleep onset, sleep end, and TST (ICC ≥ 0.825) in longitudinally followed groups. Still, generalizations are difficult due to our sample limitations.

The Ava bracelet for collection of fertility and pregnancy data in free-living conditions: An exploratory validity and acceptability study

“…These results are inconsistent with previous validity studies of consumer-grade wearables, as most have found that consumer-grade wearables generally overestimate sleep time for both adults and children. 36 , 44 , 45 Despite the acceptable MAPE value, one must also consider the clinical implications of these results. The limit of agreement indicated the Ava bracelet could underestimate sleep duration up to 1.54 h and overestimate up to 1.89 h. The American Academy of Sleep Medicine and Sleep Research Society recommends a healthy adult sleep 7 h per night for optimal health, noting that <7 h of sleep is associated with risk of obesity, diabetes, hypertension, heart disease, stroke, depression, and death.…”

The Effect of Wearable Tracking Devices on Cardiorespiratory Fitness Among Inactive Adults: Crossover Study

“…It automatically records intensity and the duration of different activity patterns, and estimates active kilocalories. It also attempts to obtain an objective estimate of stress on the basis of the root mean square of successive R-R intervals [ 20 ] and of sleep staging through a combination of accelerometer and photoplethysmography [ 21 ]. Participants were instructed to download a mobile app called “Garmin Connect” and set up a user account.…”

Predicting Wearing-Off of Parkinson’s Disease Patients Using a Wrist-Worn Fitness Tracker and a Smartphone: A Case Study

“…Then, the Garmin vivosmart4 uses heart rate variability to estimate stress levels [24,25]. The combination of the heart rate, heart rate variability, and accelerometer reading is used to estimate sleep stages [23,26]. Finally, the Garmin vivosmart4 uses the accelerometer sensor to assess the number of steps taken [27].…”