Figure 2.

Bland-Altman plots comparing sleep measures from ACT with PSG

Plots show the agreement of the ACT compared with PSG for TST (2a), WASO (2b), SOL (2c), and SE (2d). The x-axis represents the average of the sleep measures from the two devices, while the y-axis represents the difference between the two devices (i.e., ACT - PSG). Solid gray lines indicate 95% limits of agreement. Dotted lines indicate 95% confidence intervals. Each point represents a measurement pair.

Abbreviations: ACT=Actigraph; PSG=Polysomnography; SE=sleep efficiency; SOL=sleep onset latency; TST=total sleep time; WASO=wake after sleep onset.