Sleep Initiation and Maintenance Disorders: Shumaker SA

Levine DW, Dailey ME, Rockhill B, Tipping D, Naughton MJ, Shumaker SA. · University of South Carolina, 1334 Sumter St., Columbia, SC 29201, USA. · Psychosom Med. · Pubmed #15673630 links to  free full text

Abstract: OBJECTIVE: The objective of this study was to evaluate the construct validity of the five-item Women's Health Initiative Insomnia Rating Scale (WHIIRS) by comparing women taking hormone therapy (HT) versus those taking a placebo and by comparing women known to differ in vasomotor symptoms. METHODS: The WHIIRS was included in two phase III randomized trials intended to evaluate the efficacy of a combination estradiol plus and norethindrone acetate transdermal delivery system in reducing vasomotor symptoms. In all, 850 healthy postmenopausal women participated in these studies. Both trials were double-blind, one was placebo-controlled and the other was positive-controlled. The former trial admitted women with > or =8 hot flashes/day and lasted 12 weeks with data collected on the WHIIRS at baseline, 4, 8, and 12 weeks. The other trial had no entry criteria pertaining to hot flashes and lasted 52 weeks with WHIIRS data collected at baseline, 12, 24, and 52 weeks. RESULTS: The WHIIRS was sensitive to the effect of HT on sleep disturbance over time. The WHIIRS also detected differences in self-reported sleep disturbance between women with mild vasomotor symptoms compared with those with moderate to severe symptoms. As expected, the study using a positive control revealed that sleep improved over time (p <.0001). Also as predicted, the study using a placebo control found that sleep disturbance in the treatment groups improved at a faster rate than in the control groups (p = .035). CONCLUSION: The construct validity of the WHIIRS was supported because it was successfully used to detect self-reported sleep disturbance differences in women taking HT versus those taking a placebo as well as in groups known to differ in severity of their vasomotor symptoms.

Levine DW, Kripke DF, Kaplan RM, Lewis MA, Naughton MJ, Bowen DJ, Shumaker SA. · Department of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA. · Psychol Assess. · Pubmed #12847774 No free full text.

Abstract: 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 DW, Kaplan RM, Kripke DF, Bowen DJ, Naughton MJ, Shumaker SA. · Department of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA. · Psychol Assess. · Pubmed #12847773 No free full text.

Abstract: 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.