Validation of a 3-Factor scoring model for the Pittsburgh Sleep Quality Index in Older Adults

University of California, Cousins Center for Psychoneuroimmunology, Los Angeles, CA 90095-7076, USA.
Sleep (Impact Factor: 4.59). 02/2006; 29(1):112-6.
Source: PubMed


The Pittsburgh Sleep Quality Index (PSQI) is widely used to assess subjective sleep disturbances in psychiatric, medical, and healthy adult and older adult populations. Yet, validation of the PSQI single-factor scoring has not been carried out.
The PSQI was administered as a self-report questionnaire. Using a cross-validation approach, scores from the PSQI were analyzed with exploratory and confirmatory factor analyses.
San Diego, Denver, and Los Angeles community-based clinics.
Community-dwelling depressed and nondepressed adults older that 60 years of age (N = 417)
Results yielded a 3-factor scoring model that obtained a measure of perfect fit and was significantly better fitted than either the original single-factor model or a 2-factor model. Components of the 3 factors were characterized by the descriptors sleep efficiency, perceived sleep quality, and daily disturbances.
These findings validate the factor structure of the PSQI and demonstrate that a 3-factor score should be used to assess disturbances in three separate factors of subjective sleep reports.

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Available from: Michael R Irwin, Mar 16, 2014
    • "Higher PSQI values thereby indicate worse sleep quality. To address the study aim concerning potential sleep dimension-specific effects on cortisol stress responses, subscales aligning with components identified by Cole et al. (2006) as a result of a principal component analysis of the PSQI were assessed (Cole et al., 2006). These include ''average hours of sleep'' (During the past month, how many hours of actual sleep did you get at night?), ''sleep quality'' (During the past month, how would you rate your sleep quality overall?) and ''daytime dysfunction'' (During the past month, how often have you had trouble staying awake while driving, eating meals, or engaging in social activity; During the past month, how much of a problem has it been for you to keep up enough enthusiasm to get things done?). "
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    ABSTRACT: Given the well-documented deleterious health effects, poor sleep has become a serious public health concern and increasing efforts are directed toward understanding underlying pathways. One potential mechanism may be stress and its biological correlates; however, studies investigating the effects of poor sleep on a body's capacity to deal with challenges are lacking. The current study thus aimed at testing the effects of sleep quality and quantity on cortisol responses to acute psychosocial stress. A total of 73 college-aged adults (44 females) were investigated. Self-reported sleep behavior was assessed via the Pittsburgh Sleep Quality Index and salivary cortisol responses to the Trier Social Stress Test were measured. In terms of sleep quality, we found a significant three-way interaction, such that relative to bad sleep quality, men who reported fairly good or very good sleep quality showed blunted or exaggerated cortisol responses, respectively, while women's stress responses were less dependent on their self-reported sleep quality. Contrarily, average sleep duration did not appear to impact cortisol stress responses. Lastly, participants who reported daytime dysfunctions (i.e. having trouble staying awake or keeping up enthusiasm) also showed a trend to blunted cortisol stress responses compared to participants who did not experience these types of daytime dysfunctions. Overall, the current study suggests gender-specific stress reactivity dysfunctions as one mechanism linking poor sleep with detrimental physical health outcomes. Furthermore, the observed differential sleep effects may indicate that while the body may be unable to maintain normal hypothalamic-pituitary-adrenal functioning in an acute psychosocial stress situation after falling prey to low sleep quality, it may retain capacities to deal with challenges during extended times of sleep deprivation.
    Stress (Amsterdam, Netherlands) 09/2015; DOI:10.3109/10253890.2015.1087503 · 2.72 Impact Factor
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    • "Four studies [48] [55] [62] [78] using factor analysis reported low factor loading for the SM sub-scale and another reported low factor loading for the DD sub-scale [70]. The authors reported that improved fit statistics could be obtained after removal of these items. "
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    ABSTRACT: This review appraises the process of development and the measurement properties of the Pittsburgh sleep quality index (PSQI), gauging its potential as a screening tool for sleep dysfunction in non-clinical and clinical samples; it also compares non-clinical and clinical populations in terms of PSQI scores. MEDLINE, Embase, PsycINFO, and HAPI databases were searched. Critical appraisal of studies of measurement properties was performed using COSMIN. Of 37 reviewed studies, 22 examined construct validity, 19 - known-group validity, 15 - internal consistency, and three - test-retest reliability. Study quality ranged from poor to excellent, with the majority designated fair. Internal consistency, based on Cronbach's alpha, was good. Discrepancies were observed in factor analytic studies. In non-clinical and clinical samples with known differences in sleep quality, the PSQI global scores and all subscale scores, with the exception of sleep disturbance, differed significantly. The best evidence synthesis for the PSQI showed strong reliability and validity, and moderate structural validity in a variety of samples, suggesting the tool fulfills its intended utility. A taxonometric analysis can contribute to better understanding of sleep dysfunction as either a dichotomous or continuous construct. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Sleep Medicine Reviews 02/2015; 96(10). DOI:10.1016/j.smrv.2015.01.009 · 8.51 Impact Factor
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    • "Four CFA models were specified for Time 1 and Time 2 data: the original one-factor model [5], a two-factor model [12], a three-factor model [6], and a revised one-factor model. "
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    ABSTRACT: Objective The Pittsburgh Sleep Quality Index (PSQI) is used extensively to assess subjective sleep disturbance in cancer populations. Although previous studies on the PSQI suggested a better fit for a two- or three-factor model than the original one-factor model, none accounted for the indicator-specific effect between sleep duration and habitual sleep efficiency. This study evaluated the PSQI’s dimensionality and its convergent validity with cancer-related psychopathological states in female breast cancer patients. Methods The PSQI was administered to 197 women with breast cancer. Confirmatory factor analysis examined the relative fit of one-, two-, three-, and revised one-factor models. The PSQI’s convergent validity was evaluated via bivariate correlations between the PSQI factor scores and measures of anxiety, depression, fatigue, pain, and quality of life. Results Confirmatory factor analyses showed an adequate fit for the revised one-factor model with the PSQI global score as the overall index of sleep disturbance. Although the revised one- and two-factor solutions showed statistically equivalent model fits, the one-factor model was selected due to utility reasons. The severity of sleep dysfunction that the PSQI global score represented was positively correlated with anxiety, depression, fatigue, pain, and reduced quality of life. Conclusion The results support the PSQI’s original unidimensional structure, demonstrating that the PSQI global score is a valid and parsimonious measure for assessing and screening sleep dysfunction in cancer patients.
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