The Epworth Sleepiness Scale (ESS) is a
scale intended to measure daytime
sleep
Sleep is a sedentary state of mind and body. It is characterized by altered consciousness, relatively inhibited sensory activity, reduced muscle activity and reduced interactions with surroundings. It is distinguished from wakefulness by a de ...
iness that is measured by use of a very short questionnaire. This can be helpful in diagnosing
sleep disorder
A sleep disorder, or somnipathy, is a medical disorder of an individual's sleep patterns. Some sleep disorders are severe enough to interfere with normal physical, mental, social and emotional functioning. Polysomnography and actigraphy are tests ...
s. It was introduced in 1991 by Dr Murray Johns of
Epworth Hospital in
Melbourne, Australia.
The questionnaire
The questionnaire asks the subject to rate his or her probability of falling asleep on a scale of increasing probability from 0 to 3 for eight different situations that most people engage in during their daily lives, though not necessarily every day.
[ The scores for the eight questions are added together to obtain a single number. A number in the 0–9 range is considered to be normal while a number in the 10–24 range indicates that expert medical advice should be sought.][ For instance, scores of 11–15 are shown to indicate the possibility of mild to moderate ]sleep apnea
Sleep apnea, also spelled sleep apnoea, is a sleep disorder in which pauses in breathing or periods of shallow breathing during sleep occur more often than normal. Each pause can last for a few seconds to a few minutes and they happen many tim ...
, where a score of 16 and above indicates the possibility of severe sleep apnea or narcolepsy
Narcolepsy is a long-term neurological disorder that involves a decreased ability to regulate sleep–wake cycles. Symptoms often include periods of excessive daytime sleepiness and brief involuntary sleep episodes. About 70% of those affect ...
.[ Certain questions in the scale were shown to be better predictors of specific sleep disorders, though further tests may be required to provide an accurate diagnosis.][
The questionnaire was originally created with the intent to preserve the exact wording of the questionnaire to provide a standardized test and to preserve its validity; the author of the ESS recommends that the administrator of the questionnaire does not discuss the results of the ESS with the subject until it is completed, as this may affect the subject's responses on the questionnaire.
An interactive calculator is available that utilizes the 1997 version of the ESS. It automatically provides the score based on the responses to the ESS questions]
ESS interactive calculator
The Epworth Sleepiness Scale: About the ESS
/ref>
Calibration
The Epworth Sleepiness Scale has been validated primarily in obstructive sleep apnea, though it has also shown success in detecting narcolepsy
Narcolepsy is a long-term neurological disorder that involves a decreased ability to regulate sleep–wake cycles. Symptoms often include periods of excessive daytime sleepiness and brief involuntary sleep episodes. About 70% of those affect ...
and idiopathic hypersomnia
Idiopathic hypersomnia (IH) is a neurological disorder which is characterized primarily by excessive sleep and excessive daytime sleepiness (EDS). The condition typically becomes evident in early adulthood and most patients diagnosed with IH will ...
.[ It is used to measure excessive daytime sleepiness and is repeated after the administration of treatment (e.g., CPAP) to document improvement of symptoms.]narcolepsy
Narcolepsy is a long-term neurological disorder that involves a decreased ability to regulate sleep–wake cycles. Symptoms often include periods of excessive daytime sleepiness and brief involuntary sleep episodes. About 70% of those affect ...
, the Epworth Sleepiness Scale has both a high specificity (100%) and sensitivity (93.5%).
References
External links
Epworth Sleepiness Scale (official website)
1997 version of the questionnaire
described on the above site as the "standard version that can be used by most adults."
uses the 1997 version of the ESS questionnaire and published with permission from Lauren Clowney.
{{Neuropsychology tests
Sleep disorders
Mental disorders screening and assessment tools
Neuropsychological tests