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.
Reducing dietary fat, saturated fat, and sodium and increasing intakes of dietary fiber and fruits and vegetables are important for cardiopulmonary risk reduction. Behaviorally, these dietary changes are very challenging, and in different ways. Fewer than half of U.S. adults have diets meeting recommended intakes of these constituents, and many do not see a need to align their diets with recommendations. Various nutrition education and behavioral counseling approaches have been shown to facilitate changes in fat, fiber, sodium, and fruits and vegetables, but primarily in research settings and among the highly motivated. Practice-based and interdisciplinary studies are needed to refine strategies to effect long-term dietary changes, to differentiate behavioral issues for changes involving additions versus deletions from the diet, and to elucidate the roles of sensory, psychosocial, and contextual factors in adoption and maintenance.
As part of the Women's Health Initiative Study, the 5-item Women's Health Initiative Insomnia Rating Scale (WHIIRS) was developed. This article summarizes the development of the scale through the use of responses from 66,269 postmenopausal women (mean age = 62.07 years, SD = 7.41 years). All women completed a 10-item questionnaire concerning sleep. A novel resampling technique was introduced as part of the data analysis. Principal-axes factor analysis without iteration and rotation to a varimax solution was conducted for 120,000 random samples of 1,000 women each. Use of this strategy led to the development of a scale with a highly stable factor structure. Structural equation modeling revealed no major differences in factor structure across age and race-ethnic groups. WHIIRS norms for race-ethnicity and age subgroups are detailed.
27 January 2007 in Breast Cancer Research and Treatment