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Updated: May 8, 2026
08:20
Measuring Neural Mechanisms Underlying Sleep-Dependent Memory Consolidation During Naps in Early Childhood
Published on: October 2, 2019
Development and validation of the Nonrestorative Sleep Scale (NRSS)
Kate Wilkinson1, Colin Shapiro
1University of Toronto, Toronto, ON, Canada. katewilk@gmail.com
Summary
A new 12-item scale effectively measures nonrestorative sleep (NRS), a condition where sleep feels unrefreshing. The nonrestorative sleep scale (NRSS) is now a validated and reliable tool for assessing NRS.
Area of Science:
- Sleep Medicine
- Psychometrics
Background:
- Nonrestorative sleep (NRS) is the subjective experience of sleep being unrefreshing, despite normal physiological sleep patterns.
- NRS is linked to various cognitive, emotional, and medical issues.
- Currently, no public domain instrument reliably assesses NRS.
Purpose of the Study:
- Develop and validate the nonrestorative sleep scale (NRSS).
- Provide a reliable and valid public domain tool for NRS assessment.
Main Methods:
- Administered a scale to 226 sleep clinic patients and 30 controls.
- Utilized factor analysis to refine the scale to 12 items.
- Assessed internal reliability (Cronbach's alpha) and test-retest reliability.
Main Results:
- The 12-item NRSS demonstrated excellent internal reliability (α = 0.88) and good test-retest reliability (r = 0.72).
- Factor analysis identified 4 factors explaining 73.2% of variance.
- Preliminary construct validity was supported by correlations with sleep, alertness, and affect scales.
Conclusions:
- The NRSS is a valid and reliable instrument for assessing nonrestorative sleep.
- The scale provides a much-needed tool for clinical and research settings.
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