Glossary

Epworth Sleepiness Scale [ESS]

The Epworth Sleepiness Scale (ESS) is a set of questions that measures how likely you are to fall asleep in each of 8 situations. For example, you might respond to a question about dozing with an answer of 0 (would never doze), 1 (slight chance of dozing), 2 (moderate chance of dozing), or 3 (high chance of dozing). Your responses to all of the eight questions are combined for a final score, which can range between 0 and 24. Higher scores indicate higher levels of daytime sleepiness. Most doctors and scientists consider scores of 10 or higher to indicate abnormal sleepiness.