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291.
Lifestyle Education for Activity Program (LEAP) was a comprehensive, school-based intervention designed to promote physical activity in high school girls. The intervention focused on changes in instructional practices and the school environment to affect personal, social, and environmental factors related to physical activity. Multiple process evaluation tools and an organizational assessment tool were developed to monitor program implementation from a framework called the LEAP essential elements, which characterized complete and acceptable intervention delivery; secular trends were also monitored. Using process data, LEAP intervention schools were categorized into low- and high-implementing groups and compared with control schools on nine essential elements assessed at the organizational level. The Wilcoxon scores test revealed that low- and high-implementing intervention, and control schools differed significantly on two of nine administrator-reported organizational-level components: having a physical activity team and having a faculty-staff health promotion program. A mixed-model analysis of covariance indicated that, compared to control schools, a greater percentage of girls in high-implementing schools reported engaging in vigorous physical activity. Process evaluation can be used to understand the relationship between level of implementation and successful program outcome. 相似文献
292.
The factor structure of the Personal Authority in the Family System Questionnaire (PAFS-Q) has been used in numerous studies, but the factor structure has not been examined since its development in 1984. This study examined the factor structure of the PAFS-Q. Findings suggest a six-factor solution with important differences from those reported when the PAFS-Q was developed. The main differences between this study and the original factor analysis are that this study found separate Mother and Father Intimacy factors instead of a single Intergenerational Intimacy factor and the original Spousal Fusion and Spousal Intimacy factors were not separate factors in the current study. Implications and future directions for research are also discussed. 相似文献
293.
Lai DW 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2006,22(1):121-141
In Canada, there is a lack of research on gambling among the older adults from ethnic minority groups, especially the older Chinese. In this study, two research questions were used to examine gambling among the older Chinese: (1) What is the pattern of gambling among the older Chinese in Canada? (2) What are the predictors associated with gambling among the older Chinese in Canada? The data for this study were collected as part of a multi-site study on health and well-being of 2272 older Chinese in Canada. Four main questions related to gambling were used in this study. Among the 2257 participants who answered the questions on gambling, 26.6% of them reported that they gambled. Results of the hierarchical logistic regression analysis showed that being male, having lived in Canada longer, having a higher level of social support, having more service barriers, and having a stronger level of Chinese ethnic identity would increase the probability for an older Chinese to participate in gambling. Conversely, having a post-secondary and above level of education and having a higher level of life satisfaction would reduce one’s probability of gambling. Although city of residency was also significant in predicting gambling, further analysis showed that its effect was actually caused by other factors including services barriers, social support, life satisfaction, Chinese ethnic identity, and education. 相似文献
294.
Vance DE Ball KK Roenker DL Wadley VG Edwards JD Cissell GM 《Journal of aging and physical activity》2006,14(3):254-269
Falls can impair health and reduce quality of life among older adults. Although many factors are related to falling, few analyses examine causal models of this behavior. In this study, factors associated with falling were explored simultaneously using structural-equation modeling. A variety of cognitive, physical-performance, and health measures were administered to 694 older adult drivers from the state of Maryland. The observed and latent variables of age, cognitive ability, physical functioning, health, and falling behavior were used to create a causal model. The model revealed that being older was associated with declines in cognition, and such cognitive declines predicted increased falling. Similarly, poorer health was related to poorer physical functioning, which, in turn, also predicted increased falling. This model indicates that in addition to existing fall-prevention interventions aimed at improving physical functioning, interventions to improve cognition and health might also be effective. It is speculated that fear of falling, which often results in reduced mobility among older adults, might account for the lack of a direct relationship between age and falling. This hypothesis should be examined in further research. 相似文献
295.
The invisible body of queer youth: identity and health in the margins of lesbian and trans communities 总被引:1,自引:0,他引:1
How does complexity in gender and sexual identity construction and partnering practices generate unique vulnerabilities for queer-identified youth? We present two case studies from an ongoing ethnographic study of LGBTQ youth development: "Samantha," a queer-identified woman partnered with a transgender man, and "Reid," a queer-identified transgender man who has declined medical gender transitioning and who partners with lesbians and gay men. We consider the implications of these youths' locations on the margins of both lesbian and transgender communities and the challenges in providing health care and support services for queer-identified youth. 相似文献
296.
In this article, we present strategies to help combat the U.S. nursing shortage. Key considerations include providing an attractive work schedule and work environment—critical issues for retaining existing nurses and attracting new nurses to the profession—while at the same time using the set of available nurses as effectively as possible. Based on these ideas, we develop a model that takes advantage of coordinated decision making when managing a flexible workforce. The model coordinates scheduling, schedule adjustment, and agency nurse decisions across various nurse labor pools, each of differing flexibility levels, capabilities, and costs, allowing a much more desirable schedule to be constructed. Our primary findings regarding coordinated decision making and how it can be used to help address the nursing shortage include (i) labor costs can be reduced substantially because, without coordination, labor costs on average are 16.3% higher based on an actual hospital setting, leading to the availability of additional funds for retaining and attracting nurses, (ii) simultaneous to this reduction in costs, more attractive schedules can be provided to the nurses in terms of less overtime and fewer undesirable shifts, and (iii) the use of agency nurses can help avoid overtime for permanent staff with only a 0.7% increase in staffing costs. In addition, we estimate the cost of the shortage for a typical U.S. hospital from a labor cost perspective and show how that cost can be reduced when managers coordinate. 相似文献
297.
The potential for cannibalization of new product sales by remanufactured versions of the same product is a central issue in the continuing development of closed‐loop supply chains. Practitioners have no fact‐based information to guide practice at firms and academics have no studies available to use as the basis for assumptions in models. We address the cannibalization issue by using auctions to determine consumers’ willingness to pay (WTP) for both new and remanufactured products. The auctions also allow us to better understand the potential impact of offering new and remanufactured products at the same time, which provides us insights into the potential for new product cannibalization. Our results indicate that, for the consumer and commercial products auctioned, there is a clear difference in WTP) for new and remanufactured goods. For the consumer product, there is scant overlap in bidders between the new and remanufactured products, leading us to conclude that the risk of cannibalization in this case is minimal. For the commercial product, there is evidence of overlap in bidding behavior, exposing the potential for cannibalization. 相似文献
298.
Daniel Dufresne 《统计学通讯:理论与方法》2013,42(5):837-854
The family consisting of the distributions of products of two independent beta variables is extended to include cases where some of the parameters are not positive but negative or complex. This “beta product” distribution is expressible as a Meijer G function. An example (from risk theory) where such a distribution arises is given: an infinite sum of products of independent random variables is shown to have a distribution that is the product convolution of a complex-parameter beta product and an independent exponential. The distribution of the infinite sum is a new explicit solution of the stochastic equation X = (in law) B(X + C). Characterizations of some G distributions are also proved. 相似文献
299.
Statements that are inherently multiplicative have historically been justified using ratios of random variables. Although recent work on ratios has extended the classical theory to produce confidence bounds conditioned on a positive denominator, this current article offers a novel perspective that eliminates the need for such a condition. Although seemingly trivial, this new perspective leads to improved lower confidence bounds to support multiplicative statements. This perspective is also more satisfying as it allows comparisons that are inherently multiplicative in nature to be properly analyzed as such. 相似文献
300.
In this note we consider estimation of a mixture model of count data which is composed of two discrete random variables. Conditional and unconditional estimation procedures are given for estimating the unknown parameter(s) of interest using the likelihood function. Asymptotic relative efficiencies are given to examine the amount of information loss in using the two estimation procedures. Specifically, we study the change in asymptotic relative efficiency, if any, in different parameter settings. 相似文献