You must be aware that smartwatches nowadays have a new feature called sleep tracking where it claims to track the amount of sleep a person is getting and out of that, how much of it is deep sleep and from that we can determine the quality of sleep a person is getting. Now, there is a new study done on the sleep trackers used in smartwatches compared to traditional sleep trackers in order to determine the accuracy of sleep tracking done by the smartwatches and if it is reliable at all.
As per the details from the study, the investigators wanted “to determine whether automated sleep monitoring could be substituted for a sleep diary. The study included 184 overnight recordings, which were followed by an analysis by investigators; however, 10 nights were excluded from evaluation due to missing or incorrect data in the sleep diary and 8 for the smartwatch data. Objective sleep measurements were recorded with a Samsung Galaxy Watch 4 and compared to the subjective approach with a sleep diary. Investigators compared 4 sleep characteristics, including falling asleep time, waking up time, total sleep time, and sleep efficiency”.
Investigators also noted that “both methods yield inaccurate results. For example, for a sleep diary, individuals may not record the times accurately, and even in the case of smartwatches, it is possible to get inaccurate measurements, either by algorithmic or user errors.” In the study, it was also found out that “smartwatches tended to register the waking time later than those who used a sleep diary, in 114 nights out of 166. They said this could be due to the individual lying in bed with little to no movement, resulting in the watch incorrectly recording sleep time. Investigators confirmed this with a detailed analysis of the nights that corresponded with the sleep times.”
Investigators also observed that “individuals would often overestimate the time to sleep and sleep efficiency with 136 recordings and 152 recordings, respectively. They determined that this was partially due to the underestimation of the time being awake during the night, which has been evident in other studies”.
