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231.
Cross‐sectional research has shown a link between adolescent substance use and educational motivation. The purpose of the current study was to examine this link in a longitudinal sample of African American youth. The study examined the interrelationships between alcohol and both marijuana use and school motivation over the high school years and their effect on graduation in 681 African American adolescents (50.8% female). School motivation was shown to relate to subsequent alcohol use throughout high school and marijuana use early in high school. School motivation did not affect graduation status, but alcohol and marijuana use were related to a lower likelihood of graduating from high school. Some gender differences and differences among those who had tried alcohol or marijuana at the first wave as opposed to those who had not tried each substance were found. The findings support a systems model where school experiences can affect substance use, which, in turn, can affect the completion of high school.  相似文献   
232.
Limited research has directly sought the input of parents involved in the child protection system during pregnancy and with their infants. As the focus of these policies and practices, parents have a unique and important insight not available to others, so it is vital to obtain their input. As part of a larger Australian study, qualitative interviews were undertaken with 13 parents asking about their views and experiences. Parents predominantly became involved with child protection services during pregnancy through a prenatal report. Parents who previously had their newborn removed from their care described it as sudden and unexpected, leaving them distressed and unsupported post-removal, with a growing list of requirements for them to see their baby or for restoration to be considered. Domestic violence was a particular issue of concern for some mothers who expressed distress that their partners, perpetrators of violence, were allowed access to their infant with fewer requirements than for them. Improvements recommended by the parents included greater communication and preparation for the removal, better recognition of improvements in their situations and increased supports to be provided to parents both pre- and post-removal. Parental experiences provide an important guide to improving child protection practice with these families.  相似文献   
233.
Many Australians are requiring mental health care, including families, leading to long wait times in order to access support. Walk-in therapy reduces barriers to mental health support services by providing support at the time that families seek help. This paper presents a proof-of-concept study investigating the acceptability and short-term effectiveness of an online walk-in family therapy service, Walk-in Together (WIT). Part 1 of the paper describes the experiences of 44 family members from 22 families who presented to a public family therapy clinic for a virtual walk-in family therapy session. The session was conducted by a team of three experienced family therapists. Family members' experiences were sought pre-session, post-session, and at 6 weeks follow-up via survey and interview. Part 2 of the paper explores therapist perceptions (n = 7) of the WIT approach, through thematic analysis of semi-structured interview data. Post-session feedback showed 85% of family members found WIT to be helpful and 50% were optimistic about their future as a family after their WIT session. Six weeks post-session it was revealed that WIT supported planning for families in equipping them to move forward with 88% of family members reporting that they knew what to do after the session. All therapists uniformly experienced the model as offering a timely and beneficial service, suitable for diverse presentations and constellations of families. These preliminary results suggest the significant utility of this WIT intervention as a well-received and helpful service for families, who valued the easy access and rapid therapeutic response afforded by the online, walk-in delivery model. This proof-of-concept paper suggests the potential for further development and growth of WIT, as well as other mental health support services using a walk-in, telehealth model to meet the rising demand for therapeutic support for families in distress.  相似文献   
234.
The intention of this article is to highlight sources of web-based reference material and software that will aid consulting statisticians when designing clinical trials. The article includes websites that provide links to explanation of statistical concepts for non-statisticians, regulatory guidelines, and free statistical study design software.  相似文献   
235.
236.
The presented paper addresses the concept of technoscience and its possible implications for technology assessment. Drawing on the discourse about converging technologies, it formulates the assumption that a general shift within science from epistemic cultures to techno-epistemic cultures lies at the heart of the propagated convergence between nano-, bio-, info- and cogno-sciences and technologies. This shift is adequately captured—so the main thesis—by the technoscience label. The paper elaborates on the shared characteristics of the new technosciences, especially their hybrid character and their non-linear integration of basic research, object construction and technological innovation. Recent calls for new modes of technology governance (e.g. for upstream technology assessment and public participation) are discussed against the background of these technoscience characteristics. It is concluded that an adequate model of emerging technosciences and a detailed understanding of their characteristics is of paramount importance for current practices of technology assessment.  相似文献   
237.
238.
This review presents the physical performance outcomes of randomised trials investigating exercise programmes that included balance exercise for older people with dementia. A systematic literature search through five computerised bibliographic databases until February 2009 was carried out. Of 1,038 potentially relevant published articles, only seven met the inclusion criteria and were extracted. Findings from the review for a total of 632 participants showed that almost all of the included studies addressed exercise or physical activities as the main intervention; however, only two of the studies focused on balance exercise. The effect size values varied from no effect (0.00) to a large effect (3.29) of the interventions for a range of physical performance outcome measures. Findings also suggest that it is feasible to conduct exercise programmes with older people with dementia. However, further studies with more specific exercise designed to improve balance performance in order to prevent falls are required for older people with dementia.  相似文献   
239.
In cost‐effectiveness analyses of drugs or health technologies, estimates of life years saved or quality‐adjusted life years saved are required. Randomised controlled trials can provide an estimate of the average treatment effect; for survival data, the treatment effect is the difference in mean survival. However, typically not all patients will have reached the endpoint of interest at the close‐out of a trial, making it difficult to estimate the difference in mean survival. In this situation, it is common to report the more readily estimable difference in median survival. Alternative approaches to estimating the mean have also been proposed. We conducted a simulation study to investigate the bias and precision of the three most commonly used sample measures of absolute survival gain – difference in median, restricted mean and extended mean survival – when used as estimates of the true mean difference, under different censoring proportions, while assuming a range of survival patterns, represented by Weibull survival distributions with constant, increasing and decreasing hazards. Our study showed that the three commonly used methods tended to underestimate the true treatment effect; consequently, the incremental cost‐effectiveness ratio (ICER) would be overestimated. Of the three methods, the least biased is the extended mean survival, which perhaps should be used as the point estimate of the treatment effect to be inputted into the ICER, while the other two approaches could be used in sensitivity analyses. More work on the trade‐offs between simple extrapolation using the exponential distribution and more complicated extrapolation using other methods would be valuable. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
240.
Immigration reforms in the United States initiated in the 1960s are widely thought to have opened the door to mass immigration from Asia and Latin America by eliminating past discriminatory policies. While this may be true for Asians, it is not the case for Latin Americans, who faced more restrictions to legal migration after 1965 than before. The boom in Latin American migration occurred in spite of rather than because of changes in US immigration law. In this article we describe how restrictions placed on the legal entry of Latin Americans, and especially Mexicans, set off a chain of events that in the ensuing decades had the paradoxical effect of producing more rather than fewer Latino immigrants. We offer an explanation for how and why Latinos in the United States, in just 40 years, increased from 9.6 million people and 5 percent of the population to 51 million people and 16 percent of the population, and why so many are now present without authorization.  相似文献   
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