How is sleep efficiency calculated?

Sleep efficiency is a crucial metric used to evaluate sleep quality and is calculated as the ratio of total sleep time (TST) to total recording time (TRT). Total sleep time refers to the amount of time spent asleep, while total recording time encompasses the entire duration of a sleep study, including both sleep and wake periods.

To determine sleep efficiency, one divides the total sleep time by the total recording time and then multiplies the result by 100 to express it as a percentage. A higher percentage indicates better sleep efficiency, reflecting a greater proportion of the sleep study time spent sleeping as opposed to being awake.

By focusing on the ratio of TST to TRT, sleep professionals can assess how well an individual is utilizing their time in bed for actual sleep, which is essential for diagnosing and treating various sleep disorders.