What Does Sleep Efficiency (SE) Mean?
Sleep efficiency (SE) refers to the amount of time a person is actually asleep during the time spent trying to sleep. To determine sleep efficiency, a person's total sleep time (TST) is compared his or her time in bed (TIB). This ratio of sleep to wakefulness indicates how much rest a person is getting. A person who is asleep during most of the TIB is sleep efficient.
WorkplaceTesting Explains Sleep Efficiency (SE)
Sleep efficiency is one of the metrics examined during a sleep study. During a sleep study, the number of minutes spent from "lights out" in the evening of one day to "lights on" time the following morning is the time in bed (TIB). The minutes spent sleeping during the TIB are combined to arrive at a total sleep time (TST) for the person. In this controlled setting it is assumed that all TIB is spent attempting to fall asleep.
In non-clinical settings, other factors may influence the calculation of sleep efficiency (SE). Ideally, time in bed not spent attempting to fall asleep (such as reading or watching television) would be excluded from the TIB figure in calculating SE. Conversely, time spent out of bed during sleep disturbances (such as getting a drink of water in the middle of the night) would be included.
A sleep efficiency of 85% is considered normal. A rating of less than 85% is an indication that the person may not be getting enough rest. In addition to sleep studies, recording sleep activity in a sleep diary may be used to track sleep patterns for the calculation of sleep efficiency.
Employees with low sleep efficiency may suffer from daytime drowsiness, emotional disturbances, and low attention spans.