Normative values of the German Epworth Sleepiness Scale

Abstract

The Epworth Sleepiness Scale (ESS) is a widespread, self-administered questionnaire to measure the tendency to fall asleep in 8 different activities of daily life. A German version of the scale is provided by the German Sleep Research Society, but normative data for this version are lacking. Within the context of a multicenter study aiming at collecting normative data on a monotonous sustained attention test, 239 healthy subjects (120 males, 119 females) aged between 20 to 79 years completed the German Version of the Epworth Sleepiness Scale. At least 20 subjects from each age decade and gender were tested; only in the group of 70 to 79 years of age was the sample size smaller (16 males and 10 females). All subjects were screened for sleep disorders by the Pittsburgh Sleep Quality Index and the Landecker Sleep Disorders Inventory and for depression and anxiety by the Zung self-rating scales. Exclusion criteria comprised the presence of sleep disorders, shift-work, irregular sleep-wake patterns and chronic illness as well as the use of CNS active substances, and excessive caffeine or nicotine consumption. Statistical analysis revealed no differences between age and gender groups. The ESS total score for all subjects was 6.6±3.5 (SD). 85% of subjects scored <11,which corresponds to the recommended cut-off score of other studies in healthy subjects.