This article points out a trend I've seen in my practice with some of my patients. Patient, typically with insomnia, describe their sleep quality based on what their FitBit watch tells them, rather than on their own perception of their sleep quality. The problem with these wearable sleep-tracking devices is that they are not very accurate at measuring sleep - they only record movements. Those movements could be from the patient, their bedpartner, or a pet in the bed.
The article highlights 3 separate patients who put more trust in their sleep-tracking device rather than on more accurate diagnostic tools (like sleep studies) and the sleep therapist who was using validated treatments like cognitive-behavioral therapy for insomnia (CBT-I). The study authors are concerned that these sleep-tracking devices are interfering with CBT-I, reinforcing sleep-related anxiety or perfectionism for some patients. For example, they explained how all three patients were spending excessive time in bed in an attempt to increase sleep duration as measured by their sleep-tracking device. But spending excess time in bed is one of the behaviors that worsens insomnia.
The authors explained what they tell their patients about the sleep tracking devices - that the trackers measure movement and not brainwaves. Therefore, these devices cannot determine light from deep sleep. They explain that the best use of these devices is probably to monitor their sleep patterns, including how much time they are spending in bed, rather than the number of minutes spent awake or asleep.