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771.
Under certain conditions, many multiple contrast tests based on the difference of treatment means can also be conveniently expressed in terms of ratios. In this paper, a Williams test for trend is defined as ratios-to-control for ease of interpretation and to obtain directly comparable confidence intervals. Simultaneous confidence intervals for percentages are particularly helpful for interpretations in the case of multiple endpoints. Methods for constructing simultaneous confidence intervals are discussed under both homogeneous and heterogeneous error variances. This approach is available in the R extension package mratios. The proposed method is used to test for trend in an immunotoxicity study with several endpoints as an example. 相似文献
772.
This continuing education course for professionals involved in all areas of clinical trials integrates concepts related to the role of randomization in the scientific process. The course includes two interactive lecture and discussion sections and a workshop practicum. The first interactive lecture introduces basic clinical trial issues and statistical principles such as bias, blinding, randomization, control groups, and the importance of formulating clear and discriminating clinical and statistical hypotheses. It then focuses on the most commonly used clinical study designs and the corresponding patient randomization schemes. The second interactive lecture focuses on the implementation of randomization of patients and drug supply through allocation and component ID schedules. The workshop practicum, conducted in small groups, enables students to apply the lecture concepts to real clinical studies. Flexibility was built into the workshop practicum materials to allow the course content to be customized to specific audiences, and the interactive lecture sessions can be stretched to cover more advanced topics according to class interest and time availability. 相似文献
773.
Qu Y 《Pharmaceutical statistics》2011,10(3):232-235
Stratified randomization based on the baseline value of the primary analysis variable is common in clinical trial design. We illustrate from a theoretical viewpoint the advantage of such a stratified randomization to achieve balance of the baseline covariate. We also conclude that the estimator for the treatment effect is consistent when including both the continuous baseline covariate and the stratification factor derived from the baseline covariate. In addition, the analysis of covariance model including both the continuous covariate and the stratification factor is asymptotically no less efficient than including either only the continuous baseline value or only the stratification factor. We recommend that the continuous baseline covariate should generally be included in the analysis model. The corresponding stratification factor may also be included in the analysis model if one is not confident that the relationship between the baseline covariate and the response variable is linear. In spite of the above recommendation, one should always carefully examine relevant historical data to pre-specify the most appropriate analysis model for a perspective study. 相似文献
774.
775.
Ruth N. López Turley Matthew Desmond Sarah K. Bruch 《Journal of marriage and the family》2010,72(5):1377-1390
If today there exists a single transcendent idea about the family‐school connection, it is that a positive parent‐child relationship improves children's chances of succeeding in school. However, using data from the Texas Higher Education Opportunity Project (N = 5,836), we demonstrate that, although positive parent‐child relations are associated with better academic achievement in high school, they also are associated with an increased desire to live at home during college, which in turn decreases students' chances of enrolling in a 4‐year college. Furthermore, we replicated some of these associations using the National Longitudinal Study of Adolescent Health (N = 10,120), demonstrating that positive family dynamics can influence educational outcomes in potentially divergent and unanticipated directions. 相似文献
776.
Judy Layland 《Children & Society》2010,24(5):386-399
Recent models relating to the affordance of children’s participation rights, based on articles 12 and 13 of the United Nations Convention on the Rights Of the Child (1989) , have focused on the role of and strategies used by the adults working with children (Children and Society 10 , 2001: 107–117; Children and Society 20 , 2006: 209–222). Whilst these adults play a pivotal role in affording participation rights, children, and their parents/family/whānau, play an equally important role. This paper explores the complex interplay of roles, relationships, and strategies used by adults and children in home‐based education settings in Aotearoa/New Zealand, that support the affordance of participation rights for children. It identifies key aspects of practice that underpin this, and presents an alternative model of participation that is in keeping with a sociocultural approach to children’s learning and development, and acknowledges them, in the right conditions, as having a voice and agency as citizens in their own right. 相似文献
777.
This article outlines why sustainable development matters for children and young people, and explores the relevant policy context in England and the UK. It asks whether enough is being carried out by central government to secure a more sustainable future for, and with, today’s children. More is needed at the national policy level to: embed sustainable living principles within a range of policy frameworks affecting children and young people; provide a clear strategy for empowering children and young people to lead change and take action on climate change and environmental issues; and address the impact of environmental degradation on disadvantaged groups of children and young people. 相似文献
778.
Simon Lapierre 《Child Abuse Review》2010,19(5):342-357
So far, limited work has focused on women's experiences of mothering in the context of domestic violence. This article presents the findings of a study that investigated women's experiences of mothering in the context of domestic violence and, while it accounts for the difficulties and challenges these women face, it emphasises their desire to be ‘good’ mothers and the strategies they develop in order to achieve ‘good’ mothering. The findings demonstrate that abused women typically strive to be ‘good’ mothers, which requires them to put their children first and to protect and care for them. The recognition of these strategies provides ground to question current professional practices and to develop interventions that will best support women and children living with domestic violence. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
779.
Rand D. Conger Katherine J. Conger Monica J. Martin 《Journal of marriage and the family》2010,72(3):685-704
Research during the past decade shows that social class or socioeconomic status (SES) is related to satisfaction and stability in romantic unions, the quality of parent‐child relationships, and a range of developmental outcomes for adults and children. This review focuses on evidence regarding potential mechanisms proposed to account for these associations. Research findings reported during the past decade demonstrate support for an interactionist model of the relationship between SES and family life, which incorporates assumptions from both the social causation and social selection perspectives. This review concludes with recommendations for future research on SES, family processes, and individual development in terms of important theoretical and methodological issues yet to be addressed. 相似文献
780.
The past decade brought a remarkable increase in the number and quality of biosocial studies of family processes. The current review summarizes recent advances in biosocial family research by providing key exemplars of emerging research paradigms. Research in the past decade has substantiated the claim in the previous Decade Review ( Booth, Carver, & Granger, 2000 ) that bidirectional influences between all levels of analysis are paramount. There is an emerging consensus that integrating factors at multiple biological and social levels is highly informative. Because ignoring biological factors often will underestimate mediating or moderating mechanisms, the review provides recommendations for biosocial family research. We also highlight the need for researchers who understand complex family environments to lend their expertise to biosocial studies. 相似文献