sleep efficiency
A polysomnographic parameter calculated as the percentage of total sleep time relative to the total time spent in bed during a sleep study.
Full Definition
Sleep efficiency is a key quantitative measure derived from polysomnographic studies that reflects the quality and continuity of sleep. It is calculated by dividing the total sleep time by the total time in bed and expressing the result as a percentage. Normal sleep efficiency typically exceeds 85% in healthy adults, with values below 80% generally considered indicative of sleep disturbance. This parameter is affected by factors such as sleep onset latency, number and duration of awakenings, and early morning awakening. Sleep efficiency is used to assess the severity of sleep disorders, monitor treatment effectiveness, and compare sleep quality across different populations. It provides an objective measure that complements subjective sleep quality reports.
Usage
Usage note: Use lowercase unless at beginning of sentence; always express as percentage
In Context
- "The patient's sleep efficiency of 65% indicated significant sleep fragmentation and poor sleep quality." — Sleep study report
- "Following CPAP treatment, sleep efficiency improved from 58% to 89% over three months." — Treatment follow-up note