Epworth Sleepiness Scale

The Epworth Sleepiness Scale (ESS) is a brief, validated self-report instrument developed by Johns in 1991 to quantify the level of daytime somnolence or excessive daytime sleepiness. The ESS comprises eight items asking patients to rate the likelihood of dozing off in various everyday situations. It is the most commonly used standardized measure of daytime sleepiness in clinical practice and research.