The Pittsburgh Sleep Quality Index (PSQI) is a valid tool to use for gender comparisons of perceived sleep quality, according to study results published in the Journal of Clinical Sleep Medicine.
Study patients were from the 2012 to 2016 Midlife in the United States (MIDUS) Refresher Biomarker study — a longitudinal nationally representative survey that examines the roles played by biomedical, psychological, and social factors in the mental and physical health of adults.
Investigators sought to perform an analysis of measurement invariance of the PSQI between men and women in order to provide a necessary foundation for the evaluation of sleep differences between the genders. The study sample included a total of 861 adults. The mean patient age was 52.73 years; 47.85% of the enrollees were men. The sample was randomly divided into 2 half samples for exploratory factor analysis (EFA) and for confirmatory factor analysis (CFA).
All patients reported on their subjective sleep during the prior month with the use of 19 self-reported items of the PSQI, including 15 four-point items (eg, 0=not during the past month; 3=≥3 times a week), as well as 4 open-ended items. The use of EFA suggested a 2-factor structure of the PSQI.
In addition, the 2-factor CFA model fit the data well. Evidence that the 2-factor PSQI model was partially invariant between men and women was based on findings that the 2-factor PSQI model was invariant between men and women with respect to configuration, factor loadings, thresholds for all but one measure, and residual variances for all but one measure. Furthermore, women had higher means on latent factors, implying worse reports of subjective sleep.
The investigators concluded that overall, the measure of PSQI evaluates the same factors in a similar way among both men and women. Women, however, report worse subjective sleep compared with men. The results of this study, which support prior findings that women convey worse sleep quality than men, may help elucidate the broader gender-based discrepancies in health.
Li L, Sheehan CM, Thompson MS. Measurement invariance and sleep quality differences between men and women in the Pittsburgh Sleep Quality Index [published online October 30, 2019]. J Clin Sleep Med. pii:jc-19-00181