Association between elder abuse and poor sleep: A cross-sectional study among rural older Malaysians

Association between sleep quality and quality of life in Singapore

PURPOSE

Several studies have examined the relationship between sleep quality and health-related quality of life (HRQOL). However, there are a lack of generalizable data on this association in Singapore. Our study aimed to (1) investigate the association between sleep quality and HRQOL and (2) examine whether age moderated these associations.

METHODS

Data were obtained from nationwide Singapore Mental Health Study 2016 (n = 6126, response rate = 69.5%). Sleep quality was assessed using Pittsburgh Sleep Quality Index (PSQI) where higher scores indicate poorer sleep quality. HRQOL [Physical component summary (PCS) and Mental component summary (MCS)] were measured using 12-item Short-Form Survey. Associations were investigated using multivariable linear regression models, adjusted for sociodemographic, physical, and mental comorbidities. Interactions between age and sleep quality were examined by including interaction terms individually.

RESULTS

Poorer PSQI score was significantly associated with lower PCS (β = - 0.44) and lower MCS (β = - 0.73). Among PSQI components, lower PCS was significantly associated with subjective sleep quality (β = - 1.06), sleep duration (β = - 0.30), sleep disturbance (β = - 0.33), and daytime dysfunction (β = - 0.75). Lower MCS was significantly associated with subjective sleep quality (β = - 1.36), sleep latency (β = - 0.24), sleep disturbance (β = - 0.16), using of sleeping medication (β = - 1.12), and daytime dysfunction (β = - 2.08). Age moderated the association between PSQI score with PCS and MCS. Stronger association between PSQI score and MCS was observed in younger individuals (β = - 0.90) than older adults (β = - 0.45).

CONCLUSION

Our study found that poor sleep quality was associated with HRQOL of certain age groups more than others. Future studies may identify potential mediators to help people with chronic sleep problems.

On tackling abuse of older people: The forensic challenges in fatal cases investigation

The World Health Organization recently presented the priorities for tackling abuse of older people in a coordinated and strategic way. However, data on the forensic scenario is still lacking. In this context, the aim of the present work was to provide a comprehensive literature review of this inherently complex phenomenon in the post-mortem setting, in order to better characterize it from a forensic point of view. A comprehensive literature search was performed in three electronic databases following the PRISMA guidelines. Sociodemographic and medical data of victims and perpetrators, post-mortem data, types of abuse and risk factors were extracted from non-aggregated data. Forty-eight papers dealing with abuse in the post-mortem setting were included, with a predominance of case reports and case series. The review showed that neglect was the most common type of abuse and victims are predominantly older women who are abused in a domestic setting by trusted family member. To generate more and better data, expanded research in the forensic field requires standardized methods and the raise of professional awareness about abuse of older people.

Predictors of maternal satisfaction with labor induction: A prospective observational cohort study

OBJECTIVE

To identify independent predictors of maternal satisfaction with labor induction.

METHOD

In this prospective observational cohort study, 769 women prior to their labor induction had sleep and psychological well-being assessed using Pittsburgh Sleep Quality Index and Depression, Anxiety and Stress Scales. Women were asked about the adequacy of labor induction information provided and their involvement and time pressure felt in the decision-making for their labor induction. Maternal characteristics, induction and intrapartum care measures, and labor and neonatal outcomes were also assessed. Prior to discharge, women rated their satisfaction with their birth experience.

RESULTS

A total of 34 variables were considered for bivariate analysis, with 15 found to have P < 0.05. Following adjusted analysis, 10 independent predictors of maternal satisfaction were identified: maternal education, previous cesarean delivery, maternal involvement, information provided, and decision-making time pressure regarding labor induction, amniotomy, induction to delivery interval, mode of delivery, postpartum hemorrhage, and neonatal admission. Maternal satisfaction was not associated with sleep, depression, anxiety, or stress.

CONCLUSION

The identification of independent predictors of maternal satisfaction allows for patient selection, targeting of specific preinduction and intrapartum care, and focus on induction methods that can reduce induction to delivery interval, cesarean birth, and delivery blood loss to maximize women's satisfaction with labor induction.

Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research

STUDY OBJECTIVES

This review aims to assess the association between socioeconomic status (SES) and sleep health in the general population and the mediating effects of lifestyle and mental and physical health in this relationship.

METHODS

Observational studies testing the independent association between objective or subjective SES indicators and behavioral/physiological or clinical sleep health variables in the general population were included. PubMed/MEDLINE was searched for reports published from January 1990 to December 2019. The direction of effect was used as the primary effect measure, testing the hypothesis that low SES is associated with poor sleep health outcomes. Results are presented in the form of direction effect plots and synthesized as binomial proportions.

RESULTS

Overall, 336 studies were identified. A high proportion of effects at the expected direction was noted for measures of sleep continuity (100% for sleep latency, 50-100% for awakenings, 66.7-100% for sleep efficiency), symptoms of disturbed sleep (75-94.1% for insomnia, 66.7-100% for sleep-disordered breathing, 60-100% for hypersomnia), and general sleep satisfaction (62.5-100%), while the effect on sleep duration was inconsistent and depended on the specific SES variable (92.3% for subjective SES, 31.7% for employment status). Lifestyle habits, chronic illnesses, and psychological factors were identified as key mediators of the SES-sleep relationship.

CONCLUSIONS

Unhealthy behaviors, increased stress levels, and limited access to health care in low-SES individuals may explain the SES-sleep health gradient. However, the cross-sectional design of most studies and the high heterogeneity in employed measures of SES and sleep limit the quality of evidence. Further research is warranted due to important implications for health issues and policy changes.

CITATION

Papadopoulos D, Etindele Sosso FA. Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research. J Clin Sleep Med. 2023;19(3):605-620.

A Scoping Review and Conceptual Framework Examining the Role of Sleep Disturbance in Financial Exploitation in Older Adults

Sleep disturbances and financial exploitation have both been linked to impaired cognitive ability, loneliness, and depressed mood in older adults, suggesting a potential role of sleep disturbances in increasing vulnerability to financial exploitation. We sought to identify evidence linking sleep disturbances to financial exploitation. We conducted a systematic search of MEDLINE, PubMed Central, and National Center for Biotechnology Information Bookshelf for relevant published articles on sleep and financial exploitation. Three studies examining both sleep and financial exploitation were identified. None of the studies explored sleep disturbances as a cause of financial exploitation. More work needs to be done to examine the role of sleep disturbances in financial exploitation. We propose a conceptual framework for identifying possible associations among sleep disturbance, biopsychosocial, and decision-related situational factors to guide further exploration of relationships between sleep and financial exploitation.

Development of a Conceptual Framework for Severe Self-Neglect (SN) by Modifying the CREST Model for Self-Neglect

Self-neglect is an inability or refusal to meet one's own basic needs as accepted by societal norms and is the most common report received by state agencies charged with investigating abuse, neglect and exploitation of vulnerable adults. Self-neglect is often seen in addition to one or multiple conditions of frailty, mild to severe dementia, poor sleep and depression. While awareness of elder self-neglect as a public health condition and intervention has significantly risen in the past decade as evidenced by the increasing amount of literature available, research on self-neglect still lacks comprehensiveness and clarity since its inception to the medical literature in the late 1960s. With the burgeoning of the older adult population, commonness of self-neglect will most likely increase as the current incidence rate represents only the "tip of the iceberg" theory given that most cases are unreported. The COVID-19 pandemic has exacerbated the incidence of self-neglect in aged populations and the need for the use of intervention tools for aging adults and geriatric patients living alone, many of which may include in-home artificial intelligence systems. Despite this, little research has been conducted on aspects of self-neglect other than definition and identification. Substantial further study of this disorder's etiology, educating society on early detection, and conceivably preventing this syndrome altogether or at least halting progression and abating its severity is needed. The purpose of this research is to provide a definition of severe self-neglect, identify key concepts related to self-neglect, comprehensively describe this syndrome, present a conceptual framework and analyze the model for its usefulness, generalizability, parsimony, and testability.

Psychological state during pregnancy is associated with sleep quality: preliminary findings from MY-CARE cohort study

Psychological distress during pregnancy may increase the risk of adverse maternal and infant outcomes. Past studies have demonstrated the association between circadian disturbances with psychological health. However, the roles of chronotype and social jetlag on psychological state during pregnancy are yet to be identified. We aimed to examine the psychological state in pregnant women and its relations to chronotype, social jetlag (SJL), sleep quality and cortisol rhythm. The current study included a subsample of participants from an ongoing cohort study. A total of 179 primigravidas (mean age 28.4 ± 4.0 years) were recruited. Chronotype and sleep quality during the second trimester were assessed using the Morning-Eveningness Questionnaire (MEQ) and Pittsburgh Sleep Quality Index (PSQI), respectively. SJL was calculated based on the difference between mid-sleep on workdays and free days. Psychological state of participants was evaluated using the Depression, Anxiety, and Stress Scale-21 (DASS-21). Subsamples (n = 70) provided salivary samples at 5 time points over a 24 h period during the second trimester for cortisol assay. A higher proportion of pregnant women experienced moderate to severe anxiety symptoms (n = 77, 43.0%), followed by depressive (n = 17, 9.5%) and stress (n = 14, 7.8%) symptoms. No association was observed between chronotype and psychological distress during pregnancy. There was no significant difference in cortisol rhythms in relation to psychological distress. SJL and sleep quality were significantly associated with stress symptoms among pregnant women in the second trimester. Poor sleep quality, particularly daytime dysfunction (β = 0.37, p = .006) and sleep disturbances (β = 0.23, p = .047), were significantly associated with psychological distress (depressive, anxiety and stress symptoms) during the second trimester. The findings suggest that sleep is a potential modifiable lifestyle factor that can be targeted to improve psychological health among pregnant women.

Measuring Subjective Sleep Quality: A Review

Sleep quality is an important clinical construct since it is increasingly common for people to complain about poor sleep quality and its impact on daytime functioning. Moreover, poor sleep quality can be an important symptom of many sleep and medical disorders. However, objective measures of sleep quality, such as polysomnography, are not readily available to most clinicians in their daily routine, and are expensive, time-consuming, and impractical for epidemiological and research studies., Several self-report questionnaires have, however, been developed. The present review aims to address their psychometric properties, construct validity, and factorial structure while presenting, comparing, and discussing the measurement properties of these sleep quality questionnaires. A systematic literature search, from 2008 to 2020, was performed using the electronic databases PubMed and Scopus, with predefined search terms. In total, 49 articles were analyzed from the 5734 articles found. The psychometric properties and factor structure of the following are reported: Pittsburgh Sleep Quality Index (PSQI), Athens Insomnia Scale (AIS), Insomnia Severity Index (ISI), Mini-Sleep Questionnaire (MSQ), Jenkins Sleep Scale (JSS), Leeds Sleep Evaluation Questionnaire (LSEQ), SLEEP-50 Questionnaire, and Epworth Sleepiness Scale (ESS). As the most frequently used subjective measurement of sleep quality, the PSQI reported good internal reliability and validity; however, different factorial structures were found in a variety of samples, casting doubt on the usefulness of total score in detecting poor and good sleepers. The sleep disorder scales (AIS, ISI, MSQ, JSS, LSEQ and SLEEP-50) reported good psychometric properties; nevertheless, AIS and ISI reported a variety of factorial models whereas LSEQ and SLEEP-50 appeared to be less useful for epidemiological and research settings due to the length of the questionnaires and their scoring. The MSQ and JSS seemed to be inexpensive and easy to administer, complete, and score, but further validation studies are needed. Finally, the ESS had good internal consistency and construct validity, while the main challenges were in its factorial structure, known-group difference and estimation of reliable cut-offs. Overall, the self-report questionnaires assessing sleep quality from different perspectives have good psychometric properties, with high internal consistency and test-retest reliability, as well as convergent/divergent validity with sleep, psychological, and socio-demographic variables. However, a clear definition of the factor model underlying the tools is recommended and reliable cut-off values should be indicated in order for clinicians to discriminate poor and good sleepers.

Association between night-shift work, sleep quality and health-related quality of life: a cross-sectional study among manufacturing workers in a middle-income setting

OBJECTIVES

Night-shift work may adversely affect health. This study aimed to determine the impact of night-shift work on health-related quality of life (HRQoL), and to assess whether sleep quality was a mediating factor.

DESIGN

A cross-sectional study.

SETTING

11 manufacturing factories in Malaysia.

PARTICIPANTS

177 night-shift workers aged 40-65 years old were compared with 317 non-night-shift workers.

PRIMARY AND SECONDARY OUTCOMES

Participants completed a self-administered questionnaire on socio-demographics and lifestyle factors, 12-item Short Form Health Survey V.2 (SF-12v2) and the Pittsburgh Sleep Quality Index (PSQI). The Baron and Kenny's method, Sobel test and multiple mediation model with bootstrapping were applied to determine whether PSQI score or its components mediated the association between night-shift work and HRQoL.

RESULTS

Night-shift work was associated with sleep impairment and HRQoL. Night-shift workers had significantly lower mean scores in all the eight SF-12 domains (p<0.001). Compared with non-night-shift workers, night-shift workers were significantly more likely to report poorer sleep quality, longer sleep latency, shorter sleep duration, sleep disturbances and daytime dysfunction (p<0.001). Mediation analyses showed that PSQI global score mediated the association between night-shift work and HRQoL. 'Subjective sleep quality' (indirect effect=-0.24, SE=0.14 and bias corrected (BC) 95% CI -0.58 to -0.01) and 'sleep disturbances' (indirect effect=-0.79, SE=0.22 and BC 95% CI -1.30 to -0.42) were mediators for the association between night-shift work and physical well-being, whereas 'sleep latency' (indirect effect=-0.51, SE=0.21 and BC 95% CI -1.02 to -0.16) and 'daytime dysfunction' (indirect effect=-1.11, SE=0.32 and BC 95% CI -1.86 to -0.58) were mediators with respect to mental well-being.

CONCLUSION

Sleep quality partially explains the association between night-shift work and poorer HRQoL. Organisations should treat the sleep quality of night-shift workers as a top priority area for action to improve their employees' overall wellbeing.

Reliability, Validity, and Factor Structure of Pittsburgh Sleep Quality Index in Community-Based Centenarians

BACKGROUND

The Pittsburgh Sleep Quality Index (PSQI) is a widely used self-report questionnaire that measures general sleep quality in general populations. However, its psychometric properties have yet to be thoroughly examined in longevous persons.

OBJECTIVES

This study aimed to explore the reliability, validity and factor structure of the Chinese-language version of the PSQI in community-dwelling centenarians.

METHODS

A total of 958 centenarians (mean age = 102.8 years; 81.8% females) recruited from 18 regions in Hainan, China, completed the PSQI scale. Cronbach's alpha coefficient was used to measure the internal consistency. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to explore the validity and factor structure of the PSQI in this sample. Correlations between the global PSQI score and physical function, depression symptoms, self-reported health status and subjective well-being were used to assess divergent validity.

RESULTS

The Cronbach's α coefficient of the PSQI was 0.68, and it increased to 0.78 after two components (medication use and daytime dysfunction) were removed. The Spearman correlation coefficients of the PSQI score with each component were statistically significant (P<0.01). EFA yielded a two-factor structure model of the original PSQI-7 and a one-factor structure model of the simplified PSQI-5. The one-factor model with five components (χ2/df =1.59, CFI=0.99, RMSEA=0.03) fit the data well and had good configural invariance across demographic characteristics (0.53<Δχ2<5.58, P>0.05).

CONCLUSIONS

The original PSQI showed acceptable applicability in Chinese community-dwelling centenarians, and its psychometric characteristics moderately improved after sleeping medication and daytime dysfunction were removed. Further validation studies on PSQI are needed among centenarians from varied backgrounds.

Self-Reported Sleep Quality Using the Malay Version of the Pittsburgh Sleep Quality Index (PSQI-M) In Malaysian Adults

(1) Background: The Pittsburgh Sleep Quality Index (PSQI) is a useful tool for the assessment of subjective sleep quality in non-clinical and clinical settings. This study aimed to determine sleep quality in a general Malaysian adult population using a validated Malay version of the Pittsburgh sleep quality index (PSQI-M); (2) Methods: The original PSQI was translated into Malay following forward and backward translation guidelines. The final Malay version was administered to a sample of healthy working adults (n = 106; mean age: 35.3 ± 7.6 years) without history of sleep disorders. Reliability and agreement were assessed using Cronbach’s alpha, intra-class correlations coefficient (ICC), standard error of measurement (SEM), and Bland–Altman plot. Convergent validity of PSQI-M was examined with the Malay version of Epworth sleepiness scale (ESS-M) using Pearson’s correlation coefficient; (3) Results: Overall mean PSQI global score was 5.25 ± 1.85. About 45% of the sample had PSQI global score >5, indicating poor sleep quality. Total sleep duration per night was 5.95 ± 1.05 h, below the recommended amount. Sleep quality seems to be affected by age but not gender. Internal consistency as measured by Cronbach’s alpha in the whole sample was 0.74, with test–retest reliability (ICC) of 0.58 and SEM of 1.34. The PSQI test–retest scores indicated that most of the respondents (90%) lay within the 95% limits of agreement. The PSQI-M also showed significant correlation with ESS-M scores (r = 0.37, p < 0.01); (4) Conclusion: The PSQI-M showed acceptable reliability and is valid to be used in a general Malaysian adult population. Findings also indicate that a majority of the adults in our sample were experiencing inadequate sleep, thus further research is needed to identify the factors associated with poor sleep quality.

Examining the Factor Structure of the Pittsburgh Sleep Quality Index in a Multi-Ethnic Working Population in Singapore

The Pittsburgh Sleep Quality Index (PSQI) is a widely used measure for assessing sleep impairment. Although it was developed as a unidimensional instrument, there is much debate that it contains multidimensional latent constructs. This study aims to investigate the dimensionality of the underlying factor structure of the PSQI in a multi-ethnic working population in Singapore. The PSQI was administered on three occasions (baseline, 3 months and 12 months) to full-time employees participating in a workplace cohort study. Exploratory factor analysis (EFA) investigated the latent factor structure of the scale at each timepoint. Confirmatory factor analysis (CFA) evaluated the model identified by EFA, and additionally evaluated it against a single factor and a three-factor model. The EFA identified a two-factor model with similar internal consistency and goodness-of-fit across each timepoint. In the CFA, the two- and three-factor models were both superior to the unidimensional model. The two- and three-factor models of the PSQI were reliable, consistent and provided similar goodness-of-fit over time, and both models were superior to the unidimensional measure. We recommend using the two-factor model to assess sleep characteristics in working populations in Singapore, given that it performs as well as the three-factor model and is simpler compared to the latter.

Prevalence of elder abuse in Iran: a Systematic review and meta-analysis

BACKGROUND

In the past century, elder abuse has become an important health issue and a stressful event that negatively affects the physical and mental health of the elders.

AIMS

Therefore, the present study aimed to determine the prevalence of elder abuse in Iran through systematic review and meta-analysis.

METHODS

All articles about elderly abuse in Iran since 2005-2017 were searched using the Google Scholar search engine, four Iranian databases (Magiran, IranMedex, SID) and six international English language databases(Web of Science, Cochrane, Scopus, Pubmed, Science Direct-Embase) with keywords of Elder Abuse, Elder Mistreatment, Elder Neglect, Abuse and a combination of these keywords. After examining the entry and exit criteria and qualitative evaluation of the articles, Data was analyzed by comprehensive meta-analysis (CMA) software.

FINDINGS

In a systematic review, 15 articles on elders in Iran were included in the study. The overall prevalence of elder abuse was 48.3% (with 95% confidence interval: 28.6-68.6) and the highest prevalence of elder abuse was related to the care neglect dimensionat the prevalence rate of 38.4% (with 95% confidence interval: 21.7-51.6) and the lowest prevalence rate of elder abuse was related to the rejection atthe prevalence rate of 11% (with 95% confidence interval: 6.9-17.1).

CONCLUSION

The prevalence of elder abuse among elders was high in Iran. Considering the growing elderly population in Iran, preventive measures should be considered in this regard. For this reason, community health nurses are required to provide the elderly, family and community with necessary preventive interventions in this regard.

Does abuse in late life worsen sleep quality? A two-year prospective cohort study among rural older adults

BACKGROUND

Elder abuse and neglect (EAN) is a growing public health problem, and numerous adverse health effects of abuse in late life have been documented. Little is known, however, about the impact of elder abuse on sleep quality. This study examines the longitudinal relationship between EAN and sleep quality.

METHODS

This was a 2-year prospective cohort study involving 1927 older adults in a rural Malaysian district, Kuala Pilah. A multi-stage cluster sampling strategy was employed. After 2 years, 1189 respondents were re-assessed. EAN was determined using the modified Conflict Tactic Scale, while sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

The prevalence of elder abuse was 8.1% (95% CI:6.9,9.3). Longitudinal analysis using generalized estimating equations showed that elder abuse contributed to higher PSQI scores (B:0.49, 95% CI:0.17,0.58). Sub-analyses demonstrated that psychological abuse and neglect had significant longitudinal relationships with increase of PSQI scores, while other subtypes did not.

CONCLUSION

Abuse in late life, particularly psychological abuse and neglect, result in greater PSQI scores. Even though this may imply decline in sleep quality, our findings were not considered clinically significant as they did not exceed the clinical cut-off score of five. Nevertheless, sleep quality is an important determinant of health and a predictor of mortality among older adults; thus, understanding its relationship with abuse is useful to health care providers and policy-makers in improving health services and upgrading preventive measures.

Prevalence, transitions and factors predicting transition between frailty states among rural community-dwelling older adults in Malaysia

OBJECTIVES

This study aims to describe the prevalence and transitions of frailty among rural-community dwelling older adults in Malaysia and to analyse factors associated with different states of frailty transition. Frailty was conceptualized using modified Fried phenotype from the Cardiovascular Health Study.

DESIGN

This is a prospective longitudinal study with 12-months follow up among older adults in Malaysia.

SETTING

Kuala Pilah, a district in Negeri Sembilan, which is one of the fourteen states in Malaysia.

PARTICIPANTS

2,324 community-dwelling older Malaysians aged 60 years and older.

RESULTS

The overall prevalence of frailty in this study was 9.4% (95% CI 7.8-11.2). The prevalence increased at least three-fold with every 10 years of age. This increase was seen higher in women compared to men. Being frail was significantly associated with older age, women, and respondents with a higher number of chronic diseases, poor cognitive function and low socioeconomic status (p<0.05). During the 12-months follow-up, our study showed that the transition towards greater frailty states were more likely (22.9%) than transition toward lesser frailty states (19.9%) while majority (57.2%) remained unchanged. Multivariate logistic regression analysis showed that presence of low physical activity increased the likelihood of worsening transition towards greater frailty states by three times (OR 2.9, 95% CI 2.2-3.7) and lowered the likelihood of transition towards lesser frailty states (OR 0.3, 95% CI 0.2-0.4).

CONCLUSION

Frailty is reported among one in every eleven older adults in this study. The prevalence increased across age groups and was higher among women than men. Frailty possesses a dynamic status due to its potential reversibility. This reversibility makes it a cornerstone to delay frailty progression. Our study noted that physical activity conferred the greatest benefit as a modifiable factor in frailty prevention.

Association between night-shift work, sleep quality and metabolic syndrome

Objectives

Occupational factors, particularly night-shift work, are attracting growing interest as a possible determinant of metabolic syndrome (MetS). This study aimed to determine the association between night-shift work and MetS, and assess whether sleep quality is a mediating factor.

Methods

A cross-sectional study was conducted among Malaysian manufacturing workers, aged 40–65 years old. They completed a self-administered questionnaire on sociodemographics, lifestyle and family history, and the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Waist circumference, blood pressure, fasting blood sugar, triglycerides and high-density lipoprotein levels were measured. Baron and Kenny’s method, Sobel test and multiple mediation models with bootstrapping were used to determine whether the PSQI global score or its components mediated the association between night-shift work and MetS.

Results

Of the 494 participants, 177 (36%) worked night shift and 51% were men. The prevalence of MetS was 37%. Night-shift work was independently associated with a twofold increase in the risk of MetS (adjusted OR: 1.92, 95% CI 1.24 to 2.97). However, the association between night-shift work and MetS did not appear to be modified by sex. Night-shift workers also reported significantly poorer sleep quality, longer sleep latency, shorter sleep duration, sleep disturbances and daytime dysfunction. Robust mediation analysis nonetheless showed that neither PSQI global score nor its components mediated the association between night-shift work and MetS.

Conclusion

Early screening and management of MetS and the development of programmes to improve sleep quality should be carried out among night-shift workers. Future research should investigate other modifiable mediators linking night-shift work and MetS.

Dimensionality of the Pittsburgh Sleep Quality Index: a systematic review

Background

The Pittsburgh Sleep Quality Index (PSQI) dimensionality is much debated, with the greatest number of reported factor structures. Therefore, this review appraised the methodologies of studies investigating the factor structure of the PSQI.

Material and methods

MEDLINE, PsycInfo, AJOL, BASE, Cochrane Library, Directory of Open Access Journals (Lund University), CINAHL, and Embase were searched systematically to include articles published till 23rd March, 2018. The articles with the objective of factor analysis of the PSQI (20 articles) or with a major section on the same subject (25 articles) were included. There was no limitation about participant characteristics. Descriptive analysis of articles for measures of the suitability of the data for factor analysis, details of the exploratory factor analysis (EFA) and details of the confirmatory factor analysis (CFA) was performed.

Results

The analysis used by the majority did not employ the simplest scheme for interpreting the observed data: the parsimony principle. Other shortcomings included under- or non-reporting of sample adequacy measures (11 out of 45 articles), non-use of EFA (20 out of 45 articles), use of EFA without relevant details, non-use of CFA (11 out of 45 articles), and use of CFA without relevant details. Overall, 31 out of 45 articles did not use either EFA or CFA.

Conclusion

We conclude that the various PSQI factor structures for standard sleep assessment in research and clinical settings may need further validation.

Trial registration

Not applicable because this was a review of existing literature.