Evaluating the Use of Spatial Covariance Structures in the Analysis of Cardiovascular Imaging Data

This article investigates the choice of working covariance structures in the analysis of spatially correlated observations motivated by cardiac imaging data. Through Monte Carlo simulations, we found that the choice of covariance structure affects the efficiency of the estimator and power of the test. Choosing the popular unstructured working covariance structure results in an over-inflated Type I error possibly due to a sample size not large enough relative to the number of parameters being estimated. With regard to model fit indices, Bayesian Information Criterion outperforms Akaike Information Criterion in choosing the correct covariance structure used to generate data.     

Methods to assess measurement error in questionnaires of sedentary behavior

Sedentary behavior has already been associated with mortality, cardiovascular disease, and cancer. Questionnaires are an affordable tool for measuring sedentary behavior in large epidemiological studies. Here, we introduce and evaluate two statistical methods for quantifying measurement error in questionnaires. Accurate estimates are needed for assessing questionnaire quality. The two methods would be applied to validation studies that measure a sedentary behavior by both questionnaire and accelerometer on multiple days. The first method fits a reduced model by assuming the accelerometer is without error, while the second method fits a more complete model that allows both measures to have error. Because accelerometers tend to be highly accurate, we show that ignoring the accelerometer's measurement error, can result in more accurate estimates of measurement error in some scenarios. In this article, we derive asymptotic approximations for the mean-squared error of the estimated parameters from both methods, evaluate their dependence on study design and behavior characteristics, and offer an R package so investigators can make an informed choice between the two methods. We demonstrate the difference between the two methods in a recent validation study comparing previous day recalls to an accelerometer-based ActivPal.     

Continuity and change in work-life balance choices

This paper explores the ways in which the work-life balance choices made by heterosexual couples differ in different generations, how such choices are gendered, and the extent to which 'individualization' provides an adequate conceptualization of the effects of social change on heterosexual couples. It argues that processes of individualization need to be seen in the context of changing social institutions, and that it is the de-institutionalization of 'the family' and the life course that is leading to a de-gendering of work-life balance choices. The paper draws on findings from a restudy of the family and social change and a study of the gender dimensions of job insecurity both of which were carried out in the same geographical location. The studies provide evidence of generational change in work-life balance choices and increasing occupational differentiation between heterosexual partners. This leads to a situation where increasingly choices are made which blur gendered boundaries and which has been made possible by a process of de-institutionalization of the male breadwinner family. Our findings support the contention that processes of individualization are more apparent amongst younger than older generations and that, because of changes external to the family, there is more negotiation and pragmatism amongst younger generations about work-life choices.     

Relocation stress syndrome in older adults transitioning from home to a long-term care facility: myth or reality?

Relocation stress syndrome is a nursing diagnosis characterized by symptoms such as anxiety, confusion, hopelessness, and loneliness. It usually occurs in older adults shortly after moving from a private residence to a nursing home or assisted-living facility. The primary purpose of this study was to validate the symptoms of relocation stress syndrome. Eight nursing home residents and 8 assisted-living facility residents were interviewed 2 to 10 weeks after admission, when symptoms of relocation stress syndrome are most likely to appear. Results of this study indicate that the incidence of relocation stress syndrome may be overestimated. More accurate diagnosis and treatment of depression in older adults is needed.     

A combined mixed-s-skip sampling strategy to reduce the effect of autocorrelation on the X̄ scheme with and without measurement errors

In order to reduce the effect of autocorrelation on the X¯ monitoring scheme, a new sampling strategy is proposed to form rational subgroup samples of size n. It requires sampling to be done such that: (i) observations from two consecutive samples are merged, and (ii) some consecutive observations are skipped before sampling. This technique which is a generalized version of the mixed samples strategy is shown to yield a better reduction of the negative effect of autocorrelation when monitoring the mean of processes with and without measurement errors. For processes subjected to a combined effect of autocorrelation and measurement errors, the proposed sampling technique, together with multiple measurement strategy, yields an uniformly better zero-state run-length performance than its two main existing competitors for any autocorrelation level. However, in steady-state mode, it yields the best performance only when the monitoring process is subject to a high level of autocorrelation, for any given level of measurement errors. A real life example is used to illustrate the implementation of the proposed sampling strategy.KEYWORDS: Autocorrelation, measurement errors, mixed samples strategy, multiple measurements, skipping sampling strategy, steady-state, zero-state     

Risking safety and rights: online sex work,crimes and ‘blended safety repertoires’

It has been well established that those working in the sex industry are at various risks of violence and crime depending on where they sell sex and the environments in which they work. What sociological research has failed to address is how crime and safety have been affected by the dynamic changing nature of sex work given the dominance of the internet and digital technologies, including the development of new markets such as webcamming. This paper reports the most comprehensive findings on the internet‐based sex market in the UK demonstrating types of crimes experienced by internet‐based sex workers and the strategies of risk management that sex workers adopt, building on our article in the British Journal of Sociology in 2007. We present the concept of ‘blended safety repertoires’ to explain how sex workers, particularly independent escorts, are using a range of traditional techniques alongside digitally enabled strategies to keep themselves safe. We contribute a deeper understanding of why sex workers who work indoors rarely report crimes to the police, reflecting the dilemmas experienced. Our findings highlight how legal and policy changes which seek to ban online adult services advertising and sex work related content within online spaces would have direct impact on the safety strategies online sex workers employ and would further undermine their safety. These findings occur in a context where aspects of sex work are quasi‐criminalized through the brothel keeping legislation. We conclude that the legal and policy failure to recognize sex work as a form of employment, contributes to the stigmatization of sex work and prevents individuals working together. Current UK policy disallows a framework for employment laws and health and safety standards to regulate sex work, leaving sex workers in the shadow economy, their safety at risk in a quasi‐legal system. In light of the strong evidence that the internet makes sex work safer, we argue that decriminalisation as a rights based model of regulation is most appropriate.     

Impact of mindful self-care and perceived stress on the health related quality of life among young-adult students in West Virginia

ABSTRACT

There are substantial gaps in research on Health Related Quality of Life (HRQoL) in students aged 18 and above in West Virginia. The purpose of this study is to explore the associations between mindful self-care, perceived stress, and the HRQoL in this population. We conducted a cross-sectional study between March and April 2017. We included participants who were students, aged 18 years and above, living in West Virginia and were able to answer online questions in English. Data was obtained from an online survey using a structured questionnaire, including the SF12v2®, mindful self-care scale- SHORT, and Perceived Stress Scale (PSS)-10. We applied linear regressions to determine the predictors of HRQoL (physical health and mental health) using SF12v2®. 194 participants met the inclusion criteria of the study. Mindful self-care was negatively associated with perceived stress. Better mindful self-care mediated the relationship between perceived stress and psychological well-being, controlling for gender, age, race, marital status, education level, annual household income, and chronic disease status. Perceived stress and mindful self-care were not related to the physical well-being. Better mindful self-care may safeguard against perceived stress among students aged 18 years and above. Our findings in this study recommend more mindfulness-based interventions targeted to this subpopulation to improve psychological well-being.     

Level of choice in older women’s decisions to retire or continue working and associated well-being

Retirement is a complex life transition. Women’s retirement, like their work lives, may be further complicated, for example, by family or financial obligations; they may feel forced to retire or to continue working or feel they have the choice to do so. This study examines the role of voluntary versus involuntary retirement or continued work participation among retirement-age women; specifically, the relationships between choice, work status, and well-being. Compared to women forced to retire, women who chose retirement or continuing to work had higher levels of life satisfaction. Findings highlight the importance of examining retirement within the life course context.     

DEVIL'S ADVOCACY AND DIALECTICAL INQUIRY EFFECTS ON PREDICTION PERFORMANCE: TASK INVOLVEMENT AS A MEDIATING VARIABLE

Critics of previous laboratory experiments comparing devil's advocacy (DA) to dialectical inquiry (DI) have suggested that these experiments produced misleading results because (1) they used subjects who had low levels of task involvement and (2) the DI treatment used was confusing to subjects and required further explanation to be useful. The present study examines the effects of four inquiry methods—expert (E), DA, DI, and DI with explanatory statement (DI+)—on subjects' performance at a financial prediction task. Results show that DA, DI, and DI + were superior to E when the state of the world differed significantly from assumptions underlying the expert's plan. For subjects with high task involvement, DI and DI + were more effective than E and DA. The results support some of the criticisms of previous laboratory research and suggest that future research on these decision aids should include task involvement as a factor.