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1.
Longitudinal studies are the gold standard of empirical work and stress research whenever experiments are not plausible. Frequently, scales are used to assess risk factors and their consequences, and cross-lagged effects are estimated to determine possible risks. Methods to translate cross-lagged effects into risk ratios to facilitate risk assessment do not yet exist, which creates a divide between psychological and epidemiological work stress research. The aim of the present paper is to demonstrate how cross-lagged effects can be used to assess the risk ratio of different levels of psychosocial safety climate (PSC) in organisations, an important psychosocial risk for the development of depression. We used available longitudinal evidence from the Australian Workplace Barometer (N?=?1905) to estimate cross-lagged effects of PSC on depression. We applied continuous time modelling to obtain time-scalable cross effects. These were further investigated in a 4-year Monte Carlo simulation, which translated them into 4-year incident rates. Incident rates were determined by relying on clinically relevant 2-year periods of depression. We suggest a critical value of PSC?=?26 (corresponding to ?1.4 SD), which is indicative of more than 100% increased incidents of persistent depressive disorder in 4-year periods compared to average levels of PSC across 4 years.  相似文献   
2.
Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial.  相似文献   
3.
虚拟社会与道德构建   总被引:1,自引:0,他引:1  
随着网络的普及 ,虚拟社会中人们的思想、行为、生存方式都发生了新的变化。虚拟社会具有虚拟性、自由性、开放性、非人性化的特点 ;虚拟社会的自由和民主精神、权利意识和平等意识、自主精神、奉献精神、开放思想为道德建设提供了新的生长点 ,但同时带来了一系列负效应。因此 ,道德建设要采取一系列相应的措施 ,以构造文明虚拟社会  相似文献   
4.
Herein, we propose a data-driven test that assesses the lack of fit of nonlinear regression models. The comparison of local linear kernel and parametric fits is the basis of this test, and specific boundary-corrected kernels are not needed at the boundary when local linear fitting is used. Under the parametric null model, the asymptotically optimal bandwidth can be used for bandwidth selection. This selection method leads to the data-driven test that has a limiting normal distribution under the null hypothesis and is consistent against any fixed alternative. The finite-sample property of the proposed data-driven test is illustrated, and the power of the test is compared with that of some existing tests via simulation studies. We illustrate the practicality of the proposed test by using two data sets.  相似文献   
5.
Summary. This study investigates whether there was evidence of increasing risk of still-birth with increasing paternal exposure to ionizing radiation received during employment at the Sellafield nuclear installation before the child was conceived. A significant positive association is found between the total paternal preconceptional exposure to external ionizing radiation and the risk of still-birth (after adjustment for year of birth, social class, birth order and paternal age, odds ratio at 100 mSv 1.24 (95% confidence interval 1.04–1.45)). A summary of the principal scientific findings of this study has been published in the Lancet . This paper describes in detail the statistical methods that were used in the investigation and presents the results in full.  相似文献   
6.
试论弗雷格的指称理论   总被引:1,自引:0,他引:1  
弗雷格认为专名有内涵和外延;涵义决定指称.弗雷格的概念词即为通名.弗雷格第一个将词的指称理论推广到语句上,论证了语句的内涵是其思想,外延是真值.作者认为外延论题也适用于语句.  相似文献   
7.
通过2个月的运动元记忆训练,检验其对非体育专业学生元记忆水平和动作记忆成绩的影响.结果显示运动元记忆训练能显著提高大学生运动记忆策略和记忆监控水平;结果还表明训练能明显提高大学生的艺术体操和健美操动作记忆成绩(表现在动作数量上),而且艺术体操动作记忆的训练效应大于健美操.  相似文献   
8.
李蕾 《南都学坛》2002,22(2):84-86
自改革开放以来 ,中国法律制度的发展可谓日趋完善。在这个发展过程中 ,法律移植起到了不可忽视的促进作用。在法律移植过程中应注意国外法与本国法之间的同构性和兼容性 ,做到有选择地移植 ;移植过来的法律还要面临一个“本土化”的过程 ;移植法律的同时必须注意植入与之相适应的法律精神、意识和观念。从而迅速缩小与发达国家的差距 ,促进我国法制的现代化。  相似文献   
9.
斯·茨威格的教育思想   总被引:1,自引:0,他引:1  
茨威格在其回忆录和一些小说中,对奥地利当时的教育制度、教学计划、学校、教育者、学生等都是有颇多微词的。今天再来审视茨威格对他的中小学生活的回忆,可以看出他对旧教育制度的愤懑,也不难发现其中蕴含着具有远见卓识的教育理念,这在21世纪我们大兴创新教育之际仍有借鉴作用。  相似文献   
10.
从新世纪的新要求出发 ,对高校图书馆与资料室之间的关系进行了新的探讨 ,提出自己的想法 ,意在充分发挥高校图书馆与系资料室在教学科研中的作用  相似文献   
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