Explaining the Epworth Sleepiness Scale to Staff
The Epworth Sleepiness Scale (ESS) is a simple 8-question self-administered questionnaire that measures a patient's general level of daytime sleepiness by asking them to rate their likelihood of dozing off in common daily situations, with scores ranging from 0-24. 1
How to Explain the ESS to Staff
When training staff members, emphasize these key points:
The ESS asks patients to rate their chance of dozing off (0-3 scale) in 8 everyday situations such as sitting and reading, watching TV, sitting inactive in a public place, as a passenger in a car, lying down in the afternoon, sitting and talking to someone, sitting quietly after lunch, and in a car stopped in traffic 2, 1
Each situation is scored from 0 (would never doze) to 3 (high chance of dozing), creating a total score range of 0-24
The questionnaire takes only a few minutes to complete and provides a standardized measure of average sleep propensity—essentially the probability of falling asleep across various situations 2
Staff should understand that the ESS is NOT a diagnostic test for obstructive sleep apnea (OSA), but rather a screening tool to prompt further clinical questioning 3
Cutoff Score for Positive Screening
The traditional cutoff of ESS ≥10 has poor sensitivity for OSA screening; a lower cutoff of ESS ≥8 is more appropriate for clinical populations being screened for sleep disorders. 4
Evidence-Based Rationale:
The original cutoff of ≥10 has only 66% sensitivity for detecting OSA (AHI ≥5), which is inadequate 4
Lowering the cutoff to ≥8 increases sensitivity to 76% while maintaining reasonable specificity 4
Multiple studies support ESS ≥8 as a more appropriate threshold 5, 4
Critical Caveats for Staff:
The ESS has significant limitations that staff must understand:
A negative ESS (score <8 or <10) does NOT rule out OSA—in one study, 75.9% of patients with negative ESS still had OSA, including 42% with severe disease (AHI ≥30) 6
The ESS has poor negative predictive value (only 24.1%) and overall diagnostic accuracy of just 46.2% 6
The ESS cannot confirm or exclude sleepiness on its own 3
Cultural and socioeconomic factors affect how patients answer ESS questions, which may require population-specific adjustments 5
Clinical Application Algorithm
Staff should follow this approach:
Administer the ESS as an initial screening tool, using ≥8 as the threshold for concern 4
Regardless of ESS score, directly question ALL patients about:
- Daytime sleepiness (falling asleep unintentionally during daily activities)
- Recent motor vehicle crashes or near-misses due to sleepiness, fatigue, or inattention 3
If ESS ≥8 OR positive responses to direct questioning, proceed with comprehensive sleep evaluation 3
Never rely on ESS alone—it serves best as a prompt for clinicians to initiate direct questioning, not as a standalone diagnostic tool 3
Consider combining ESS with other screening tools (like STOP-Bang or NoSAS) to improve specificity 7, 8
High-Risk Driver Identification
Staff must understand that patients with BOTH moderate-to-severe daytime sleepiness AND a previous motor vehicle crash require immediate intervention and warning about driving risks until effective therapy is instituted 3. This determination is based on clinical assessment, not ESS score alone 3.
The ESS was originally validated showing correlation with objective sleep measures like multiple sleep latency testing and polysomnography findings 2, 1, but recent evidence demonstrates it performs poorly as a standalone screening tool, particularly when negative 6.