Reliability and validity of the Women's Health Initiative Insomnia Rating Scale.
The reliability and construct validity of the 5-item Women's Health Initiative Insomnia Rating Scale (WHIIRS) were evaluated in 2 studies. In Study 1, using a sample of 66,269 postmenopausal women, validity of the WHIIRS was assessed by examining its relationship to other measures known to be related to sleep quality. Reliability of the WHIIRS was estimated using a resampling approach; the mean alpha coefficient was .78. Test-retest reliability coefficients were .96 for same-day administration and .66 after a year or more. Correlations of the WHIIRS with the other measures were in the predicted directions. Study 2 used a sample of 459 women and compared the WHIIRS with objective indicators of sleep quality. Results showed that differences in the objective indicators could be detected by the WHIIRS. Findings suggest that a between-group mean difference of approximately 0.50 of a standard deviation on the WHIIRS may be clinically meaningful.
Levine
Douglas W
DW
Department of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA. dlevine@wfubmc.edu
Kripke
Daniel F
DF
Kaplan
Robert M
RM
Lewis
Megan A
MA
Naughton
Michelle J
MJ
Bowen
Deborah J
DJ
Shumaker
Sally A
SA
D000368:Aged; D005260:Female; D006801:Humans; D008875:Middle Aged; D011159:Population Surveillance; D017698:Postmenopause; D011594:Psychometrics; D015203:Reproducibility of Results; D012494:Sampling Studies; D007319:Sleep Initiation and Maintenance Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D016387:Women's Health