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991.
Oliver N. Keene Stephen Ruberg Alexander Schacht Mouna Akacha Rachael Lawrance Anna Berglind David Wright 《Pharmaceutical statistics》2020,19(4):370-387
In drug development, we ask ourselves which population, endpoint and treatment comparison should be investigated. In this context, we also debate what matters most to the different stakeholders that are involved in clinical drug development, for example, patients, physicians, regulators and payers. With the publication of draft ICH E9 addendum on estimands in 2017, we now have a common framework and language to discuss such questions in an informed and transparent way. This has led to the estimand discussion being a key element in study development, including design, analysis and interpretation of a treatment effect. At an invited session at the 2018 PSI annual conference, PSI hosted a role‐play debate where the aim of the session was to mimic a regulatory and payer scientific advice discussion for a COPD drug. Including role‐play views from an industry sponsor, a patient, a regulator and a payer. This paper presents the invented COPD case‐study design and considerations relating to appropriate estimands are discussed by each of the stakeholders from their differing viewpoints with the additional inclusion of a technical (academic) perspective. The rationale for each perspective on approaches for handling intercurrent events is presented, with a key emphasis on the application of while‐on‐treatment and treatment policy estimands in this context. It is increasingly recognised that the treatment effect estimated by the treatment policy approach may not always be of primary clinical interest and may not appropriately communicate to patients the efficacy they can expect if they take the treatment as directed. 相似文献
992.
In this overview of Volume 64, Issue 1, of the Journal of Social Issues , we describe why it is important to consider the diversity of student pathways through time and in context and why it is important to focus particularly on youth who defy predictions. We describe the ways in which expectations are formed in statistical analysis and also in real-world education systems and how the structural rigidity inherent in such systems can lead to poor person–environment fit for young people in education or training and to misleading statistical analysis. Our intention is to move beyond analytic approaches that assume "one size fits all" while recognizing both that policy cannot provide fully individualized environments for everyone and that research cannot focus only on the unique characteristics of each individual. By focusing on individuals for whom our models typically do not apply, we highlight the value of research on complex but meaningful patterns of commonality among people, not in terms of the average person or effects, but in terms of coherent, distinct, and relatively homogenous subgroups of people experiencing systematic and consequential differences in their lives and lifepaths . 相似文献
993.
Stephen C. Peck Robert W. Roeser Nicole Zarrett Jacquelynne S. Eccles 《The Journal of social issues》2008,64(1):135-156
This longitudinal study examines how extracurricular activity involvement contributes to "educational resilience"—the unexpected educational attainments of adolescents who are otherwise vulnerable to curtailed school success due to personal- and social-level risks. Educationally vulnerable youth characterized by significant risks and an absence of assets were identified during early adolescence (approximately age 14) using measures of academic motivation, achievement, and mental health as well as family, school, and peer contexts. Using a mixture of variable- and pattern-centered analytic techniques, we investigate how both the total amount time that vulnerable youth spent in positive extracurricular activities and the specific pattern of their extracurricular activity involvement during late adolescence (approximately age 17) predict their subsequent enrollment in college during early adulthood (up through approximately age 21). Educational resilience was predicted uniquely by some, but not all, activity patterns. These results suggest that positive extracurricular activity settings afford vulnerable youth developmentally appropriate experiences that promote educational persistence and healthy development . 相似文献
994.
The traditional formulation of the altruism model has altruistic terms that relate solely to other parties’ felicities from consumption. But if those others are altruistic as well, their altruism benefits are being neglected. Total altruism takes the total utilities of others, rather than their mere felicities, as the basis for altruistic valuations. We assess total altruism in an intergenerational world. Perfect altruism, a concept due to Ramsey (Econ. J. 38(152):543–559, 1928), requires that a generation value itself relative to its successor as it would any two consecutive generations. Total altruism and perfect altruism prove to be incompatible concepts. Total altruism is only meaningful when there is some generational selfishness. The analysis considers both forward-looking and forward and backward-looking altruism. 相似文献
995.
The problem of patient no‐shows (patients who do not arrive for scheduled appointments) is significant in many health care settings, where no‐show rates can vary widely. No‐shows reduce provider productivity and clinic efficiency, increase health care costs, and limit the ability of a clinic to serve its client population by reducing its effective capacity. In this article, we examine the problem of no‐shows and propose appointment overbooking as one means of reducing the negative impact of no‐shows. We find that patient access and provider productivity are significantly improved with overbooking, but that overbooking causes increases in both patient wait times and provider overtime. We develop a new clinic utility function to capture the trade‐offs between these benefits and costs, and we show that the relative values that a clinic assigns to serving additional patients, minimizing patient waiting times, and minimizing clinic overtime will determine whether overbooking is warranted. From the results of a series of simulation experiments, we determine that overbooking provides greater utility when clinics serve larger numbers of patients, no‐show rates are higher, and service variability is lower. Even with highly variable service times, many clinics will achieve positive net results with overbooking. Our analysis provides valuable guidance to clinic administrators about the use of appointment overbooking to improve patient access, provider productivity, and overall clinic performance. 相似文献
996.
Yolanda Barbáchano D. Stephen Coad Derek R. Robinson 《Journal of statistical planning and inference》2008
Minimisation is a method often used in clinical trials to balance the treatment groups with respect to some prognostic factors. In the case of two treatments, the predictability of this method is calculated for different numbers of factors, different numbers of levels of each factor and for different proportions of the population at each level. It is shown that if we know nothing about the previous patients except the last treatment allocation, the next treatment can be correctly guessed more than 60% of the time if no biased coin is used. If the two previous assignments are known to have been the same, the next treatment can be guessed correctly around 80% of the time. Therefore, it is suggested that a biased coin should always be used with minimisation. Different choices of biased coin are investigated in terms of the reduction in predictability and the increase in imbalance that they produce. An alternative design to minimisation which makes use of optimum design theory is also investigated, by means of simulation, and does not appear to have any clear advantages over minimisation with a biased coin. 相似文献
997.
This paper proposes that the teacher, on the basis of action-research methodology, can produce two types of scientific knowledge: one based on the teacher as researcher (the teacher as ethnographer), and another based on the development of pedagogic action (the teacher as educator). The education of such a teacher, simultaneously a researcher and an educator, is carried out through the concretisation of that which has denominated the interface of intercultural education. The development of this interface renders possible the management of diversity by the teacher. This diversity is present both in the school, as well as, more specifically, in the classroom. It can also be seen as a source of wealth for the further deepening of the democratic nature of both the school and the education system. 相似文献
998.
The authors examine the usefulness of postmodernism in career counseling. Specifically, a case is made for broadening career counseling theories and techniques to feature the contextual influences inherent in each individual's unique career history. A career intervention, titled the Career‐O‐Gram, is introduced as a tool for exploring contextual influences on career development. A case study is presented to demonstrate the application of the Career‐O‐Gram. 相似文献
999.
The complex variety of experiences that characterize the current wave of immigration have prompted revisions in the classic model of straight-line assimilation; the most important alternative theory is based on the concept of "segmented" assimilation. This paper assesses the validity of these two perspectives with data on three generations of Hispanic immigrants in Houston. Contrary to the standard assimilation model, third-generation Hispanics are not staying in school longer, nor are they earning higher wages than members of the second generation. But contrary to the segmented-assimilation model, third-generation Hispanics also give no evidence at all of having assimilated into an "adversarial" culture that rejects mainstream American values and is presumably responsible for restricting their upward mobility. The data reaffirm the pivotal role of education in determining occupational mobility, and they point to the importance of identifying the external societal factors that account for the stalled progress in educational achievement among third-generation Hispanic Americans. 相似文献
1000.
Team leadership 总被引:5,自引:0,他引:5
Despite the ubiquity of leadership influences on organizational team performance and the large literatures on leadership and team/group dynamics, we know surprisingly little about how leaders create and handle effective teams. In this article, we focus on leader–team dynamics through the lens of “functional leadership.” This approach essentially asserts that the leader's main job is to do, or get done, whatever functions are not being handled adequately in terms of group needs. We explicate this functional leadership approach in terms of 4 superordinate and 13 subordinate leadership dimensions and relate these to team effectiveness and a range of team processes. We also develop a number of guiding propositions. A key point in considering such relationships is the reciprocal influence, whereby both leadership and team processes influence each other. 相似文献