Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS

Purpose: The Epworth Sleepiness Scale (ESS) is a widely used tool for measuring sleepiness. In addition to providing a single measure of sleepiness (a one-factor structure), the ESS also has the capacity to provide additional information about specific factors that facilitate sleep onset, including...

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Main Authors: Olaithe, M., Skinner, T., Clarke, J., Eastwood, Peter, Bucks, R.
Format: Journal Article
Published: 2013
Online Access:http://hdl.handle.net/20.500.11937/58410
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author Olaithe, M.
Skinner, T.
Clarke, J.
Eastwood, Peter
Bucks, R.
author_facet Olaithe, M.
Skinner, T.
Clarke, J.
Eastwood, Peter
Bucks, R.
author_sort Olaithe, M.
building Curtin Institutional Repository
collection Online Access
description Purpose: The Epworth Sleepiness Scale (ESS) is a widely used tool for measuring sleepiness. In addition to providing a single measure of sleepiness (a one-factor structure), the ESS also has the capacity to provide additional information about specific factors that facilitate sleep onset, including a person's posture, activity and environment. These features of sleepiness are referred to as somnificity. This study evaluates and compares the fit of a one-factor structure (sleepiness) and three-factor structure (reflecting low, medium and high levels of somnificity) for the ESS. Methods: All participants (a community sample N = 356 and a clinical sample N = 679) were administered the ESS. Confirmatory factor analysis was used to evaluate and compare the fit of one- and three-factor models of the ESS. Results: In both samples, a three-factor structure (community sample adjusted X 2 = 2.95, root mean square error of approximation (RMSEA) = 0.07, Comparative Fit Index (CFI) = 0.95; clinical sample adjusted X 2 = 3.98, RMSEA = 0.07, CFI = 0.98) provided a level of model fit that was at least as good as the one-factor structure (community sample adjusted X 2 = 5.01, RMSEA = 0.11, CFI = 0.87; clinical sample adjusted X 2 = 8.87, RMSEA = 0.11, CFI = 0.92). Conclusions: In addition to a single measure of sleepiness, the ESS can provide subscale scores which relate to three underlying levels of somnificity. These findings suggest that the ESS can be used to measure an individual's overall sleep propensity as well as more specific measures of sleep propensity in low, moderate and high levels of situational somnificity. © 2012 Springer-Verlag.
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spelling curtin-20.500.11937-584102017-11-24T05:46:19Z Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS Olaithe, M. Skinner, T. Clarke, J. Eastwood, Peter Bucks, R. Purpose: The Epworth Sleepiness Scale (ESS) is a widely used tool for measuring sleepiness. In addition to providing a single measure of sleepiness (a one-factor structure), the ESS also has the capacity to provide additional information about specific factors that facilitate sleep onset, including a person's posture, activity and environment. These features of sleepiness are referred to as somnificity. This study evaluates and compares the fit of a one-factor structure (sleepiness) and three-factor structure (reflecting low, medium and high levels of somnificity) for the ESS. Methods: All participants (a community sample N = 356 and a clinical sample N = 679) were administered the ESS. Confirmatory factor analysis was used to evaluate and compare the fit of one- and three-factor models of the ESS. Results: In both samples, a three-factor structure (community sample adjusted X 2 = 2.95, root mean square error of approximation (RMSEA) = 0.07, Comparative Fit Index (CFI) = 0.95; clinical sample adjusted X 2 = 3.98, RMSEA = 0.07, CFI = 0.98) provided a level of model fit that was at least as good as the one-factor structure (community sample adjusted X 2 = 5.01, RMSEA = 0.11, CFI = 0.87; clinical sample adjusted X 2 = 8.87, RMSEA = 0.11, CFI = 0.92). Conclusions: In addition to a single measure of sleepiness, the ESS can provide subscale scores which relate to three underlying levels of somnificity. These findings suggest that the ESS can be used to measure an individual's overall sleep propensity as well as more specific measures of sleep propensity in low, moderate and high levels of situational somnificity. © 2012 Springer-Verlag. 2013 Journal Article http://hdl.handle.net/20.500.11937/58410 10.1007/s11325-012-0763-6 restricted
spellingShingle Olaithe, M.
Skinner, T.
Clarke, J.
Eastwood, Peter
Bucks, R.
Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS
title Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS
title_full Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS
title_fullStr Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS
title_full_unstemmed Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS
title_short Can we get more from the Epworth Sleepiness Scale (ESS) than just a single score?: A confirmatory factor analysis of the ESS
title_sort can we get more from the epworth sleepiness scale (ess) than just a single score?: a confirmatory factor analysis of the ess
url http://hdl.handle.net/20.500.11937/58410