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71.
72.
Graphical representation of survival curves is often used to illustrate associations between exposures and time-to-event outcomes. However, when exposures are time-dependent, calculation of survival probabilities is not straightforward. Our aim was to develop a method to estimate time-dependent survival probabilities and represent them graphically. Cox models with time-dependent indicators to represent state changes were fitted, and survival probabilities were plotted using pre-specified times of state changes. Time-varying hazard ratios for the state change were also explored. The method was applied to data from the Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Survival curves showing a ‘split’ at a pre-specified time t allow for the qualitative comparison of survival probabilities between patients with similar baseline covariates who do and do not experience a state change at time t. Time since state change interactions can be visually represented to reflect changing hazard ratios over time. A2ALL study results showed differences in survival probabilities among those who did not receive a transplant, received a living donor transplant, and received a deceased donor transplant. These graphical representations of survival curves with time-dependent indicators improve upon previous methods and allow for clinically meaningful interpretation.  相似文献   
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74.
The present study uses canonical analysis to examine the contingency model of organizations in the nursing home field. Data on environmental pressures and managerial practices relevant to the decision-making process are analyzed. Results support the theory that managerial practices are contingent on environmental pressures. The implications of these results for health-care decision makers and for future assessments of managerial-environmental relationships are discussed.  相似文献   
75.
Population forecasts entail a significant amount of uncertainty, especially for long-range horizons and for places with small or rapidly changing populations. This uncertainty can be dealt with by presenting a range of projections or by developing statistical prediction intervals. The latter can be based on models that incorporate the stochastic nature of the forecasting process, on empirical analyses of past forecast errors, or on a combination of the two. In this article, we develop and test prediction intervals based on empirical analyses of past forecast errors for counties in the United States. Using decennial census data from 1900 to 2000, we apply trend extrapolation techniques to develop a set of county population forecasts; calculate forecast errors by comparing forecasts to subsequent census counts; and use the distribution of errors to construct empirical prediction intervals. We find that empirically-based prediction intervals provide reasonably accurate predictions of the precision of population forecasts, but provide little guidance regarding their tendency to be too high or too low. We believe the construction of empirically-based prediction intervals will help users of small-area population forecasts measure and evaluate the uncertainty inherent in population forecasts and plan more effectively for the future.  相似文献   
76.
This article uses privileged families who hire Independent Educational Consultants (IECs) as an instance to examine how privileged parents collaborate with individuals whom they consider educational experts to support their children in the college race. We argue that advantaged parents' anxieties about their children have created a market for IECs who provide expert advice in order to mitigate the uncertainties that these parents experience and to manage various goals that they want to achieve at an important turning point in their children's lives. Drawing primarily on interviews with parents who work with IECs, we introduce the concept of “collaborative cultivation” to analyze the processes whereby advantaged parents rely on the expertise and expert status of private counselors to cope with their and their children's vulnerability in the college race while at the same time preparing their children for the unknown future. The parental method of “concerted cultivation” reveals how elite parents rely on individuals they perceive as experts to establish “bridges” between their own social worlds and the academic worlds that appear to beyond their control. This bridging labor points to the myriad cultural beliefs enacted to justify the child‐rearing goals that privileged parents wish to accomplish by working with IECs.  相似文献   
77.
This paper critically scrutinizes the key success factors and tools described in the partnering literature by exploring how they are implemented in a public–private partnering collaboration. In addition to this the paper investigates to what extent these tools facilitate the relationship between the parties in a partnering process. The empirical data consist of two longitudinal case studies. Both cases are large and complex urban development projects in the Swedish water and sewage industry. The results from the cases were ambiguous and positive; as well, some negative outcomes were present. Further, the processes were in both cases far from easy and it required a lot of effort from the parties in the collaboration to make the collaboration work and establish a culture based on trust, especially higher up in the organization. As could be expected, the reality is thus far more complex and cumbersome than previous studies indicate.  相似文献   
78.
This study examines the relationship between premarital childbearing and the timing of women's entry into their first marriage in sub‐Saharan Africa. The study shows that African women who have a premarital birth generally experience later transitions to marriage than do their childless peers. Although the birth of a child precipitates a quicker transition to marriage initially, unmarried mothers, on average, marry at older ages than their childless peers and remain single for between 2 and 14 years. Evidence from a subsample of countries confirms that the time between having a child and first marriage has lengthened slightly in some countries; however, this reflects mainly the overall trend toward later marriage, rather than a further bifurcation of the marital trajectories of mothers versus childless women. The study raises policy concerns about the welfare of Africa's single mothers and their children.  相似文献   
79.
The purpose of this exploratory study was to expand upon previous literatures in public relations power, and fill the need for more scholarship regarding practitioners’ perceptions of social media work, power, and gender. Findings from a survey of PRSA members showed that there is a gendered difference in power perception between males and females regardless of their PR roles or level of experience, but social media expertise was perceived equally between both genders. We argue that while social media expertise may serve to reduce a gendered power divide in public relations, continued critical exploration of social media and gender inequality is necessary.  相似文献   
80.
Youth experience increased surveillance by and involuntary contact with police officers compared with other age groups. Studies that explore the experiences of youth during these encounters are scant and focus on youth with criminal histories. This research aims to explore the experiences of college-attending youth between 18 and 24 years old in two southern states. The study was designed and conducted according to the tenets of interpretative phenomenological analysis (IPA). Twelve Black youth were recruited and interviewed between April 2015 and April 2016. Three superordinate themes (and subthemes) were identified: (1) negative feelings towards the police; (2) precarity of police encounters (subthemes: police as a threat to welfare; it could be me; steps to follow during police encounters; behavior is irrelevant) and; (3) police response is part of structural racism (subthemes: racism is everywhere; media contributes to racism). The importance of these findings for social work practice and research will be discussed.  相似文献   
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