Evaluation of a consumer fitness-tracking device to assess sleep in adults

Abstract

Wearable fitness-tracker devices are becoming increasingly available. We evaluated the agreement between Jawbone UP and polysomnography (PSG) in assessing sleep in a sample of 28 midlife women. As shown previously, for standard actigraphy, Jawbone UP had high sensitivity in detecting sleep (0.97) and low specificity in detecting wake (0.37). However, it showed good overall agreement with PSG with a maximum of two women falling outside Bland-Altman plot agreement limits. Jawbone UP overestimated PSG total sleep time (26.6 ± 35.3 min) and sleep onset latency (5.2 ± 9.6 min), and underestimated wake after sleep onset (31.2 ± 32.3 min) (p's < 0.05), with greater discrepancies in nights with more disrupted sleep. The low-cost and wide-availability of these fitness-tracker devices may make them an attractive alternative to standard actigraphy in monitoring daily sleep-wake rhythms over several days.

Keywords: Actigraphy; activity trackers; motion; sleep; wristbands.

Conflict of interest statement

Authors declare no conflicts of interest. This study was performed at the SRI International (Menlo Park, CA, USA) and was supported by National Institutes of Health, Grant HL103688 to FCB.

Figures

Figure 1

Agreement (Bland-Altman plots) between Jawbone UP and polysomnography (PSG) for total sleep time (TST), sleep onset time (SOL) and wake after sleep onset (WASO) for 28 women who had a PSG recording. In the sample of 18 women with two recordings, only the first PSG night was used. Average, mean differences (or bias) between Jawbone UP and PSG outcomes, lower and upper agreement limits (mean difference ±1.96SD) and 95%CI for mean differences and agreement limits (dotted line) are displayed.