Blinded sample size re‐estimation in crossover bioequivalence trials

In drug development, bioequivalence studies are used to indirectly demonstrate clinical equivalence of a test formulation and a reference formulation of a specific drug by establishing their equivalence in bioavailability. These studies are typically run as crossover studies. In the planning phase of such trials, investigators and sponsors are often faced with a high variability in the coefficients of variation of the typical pharmacokinetic endpoints such as the area under the concentration curve or the maximum plasma concentration. Adaptive designs have recently been considered to deal with this uncertainty by adjusting the sample size based on the accumulating data. Because regulators generally favor sample size re‐estimation procedures that maintain the blinding of the treatment allocations throughout the trial, we propose in this paper a blinded sample size re‐estimation strategy and investigate its error rates. We show that the procedure, although blinded, can lead to some inflation of the type I error rate. In the context of an example, we demonstrate how this inflation of the significance level can be adjusted for to achieve control of the type I error rate at a pre‐specified level. Furthermore, some refinements of the re‐estimation procedure are proposed to improve the power properties, in particular in scenarios with small sample sizes. Copyright © 2014 John Wiley & Sons, Ltd.     

Practical approaches for design and analysis of clinical trials of infertility treatments: crossover designs and the Mantel–Haenszel method are recommended

Crossover designs have some advantages over standard clinical trial designs and they are often used in trials evaluating the efficacy of treatments for infertility. However, clinical trials of infertility treatments violate a fundamental condition of crossover designs, because women who become pregnant in the first treatment period are not treated in the second period. In previous research, to deal with this problem, some new designs, such as re‐randomization designs, and analysis methods including the logistic mixture model and the beta‐binomial mixture model were proposed. Although the performance of these designs and methods has previously been evaluated in large‐scale clinical trials with sample sizes of more than 1000 per group, the actual sample sizes of infertility treatment trials are usually around 100 per group. The most appropriate design and analysis for these moderate‐scale clinical trials are currently unclear. In this study, we conducted simulation studies to determine the appropriate design and analysis method of moderate‐scale clinical trials for irreversible endpoints by evaluating the statistical power and bias in the treatment effect estimates. The Mantel–Haenszel method had similar power and bias to the logistic mixture model. The crossover designs had the highest power and the smallest bias. We recommend using a combination of the crossover design and the Mantel–Haenszel method for two‐period, two‐treatment clinical trials with irreversible endpoints. Copyright © 2015 John Wiley & Sons, Ltd.     

L'économie des plateformes sous l'angle de la géographie ouvrière: comprendre les stratégies d'organisation collective dans le contexte du travail intermédié par les plateformes numériques

L'auteure analyse sous un angle géographique la lutte collective des travailleurs de plateforme. Distinguant deux formes de travail de plateforme (l'offre de services locaux et le microtravail), elle examine leurs caractéristiques spatiales respectives et les stratégies d'organisation collective spécifiques à chacune. À partir de trois démarches de dialogue social (comités d'entreprise, négociation collective et accords multientreprises), elle cherche à comprendre pourquoi chaque catégorie de travailleurs de plateforme choisit telle stratégie plutôt que telle autre. Elle analyse les cadres réglementaires dans lesquels s'inscrivent les luttes collectives de ces travailleurs et les chances de voir cette mobilisation améliorer leurs conditions de travail.     

论民事再审制存在的价值

“凡存在皆合理” ,我国于 1979年颁布的民事诉讼法就已确立了民事再审制。时至今日 ,随着司法改革的不断推进 ,民事再审制自身的弊端也日显端倪。对其存废 ,学者们众说纷纭。而民事再审制作为一种补救机制 ,在当前还有存在的必要与意义 ,尚有存在的条件与空间。当然 ,并不是说它的存在就能解决、避免与克服司法审判中的所有问题。但没有最好 ,只有更好 ,民事再审制的确是当前相对有效的一种补救机制。我们应该不断完善 ,以最大程度的发挥其功效。     

成都地区女工下岗问题研究

本文在 2 0 0 0年对成都地区下岗女工进行社会调查的基础上 ,分析了当前下岗女工的基本状况 ,由此就如何妥善解决下岗女工再就业问题阐述了政府和女工各自可能发挥的作用     

关于中学数学教师教育科研现状的调查与分析

本文分析中学数学教师进行教育科研的困难和问题,并提出一些意见和建议.     

A ‘Lost Crowd’: Reconfiguring the Harlem Renaissance as a Post-War ‘Lost Generation’

Abstract

Traditionally for black Americans, World War I did not signify the traumatic removal of traditional Victorian ideals, the end of any romantic notions of battle, or, as it would for white American literature, the disillusionment and alienation of a literary ‘Lost Generation’. Although experiencing continued racism upon their return, the recognition that black Americans had received in wartime France came to characterize a budding enthusiasm for the social prospects of the post-war era. Yet many novels of the Harlem Renaissance certainly resonate with the disillusionment of the Lost Generation and similarly grapple with notions of war trauma and traumatic post-war (re)integration into a chaotic American society. This article considers the endeavour to reconcile feelings of post-war national unity with the African-American struggle for racial equality in the early twentieth century. By evaluating the analogous themes of alienation, masculinity, and place represented by both the Lost Generation and Harlem Renaissance, this article seeks to highlight traumatic parallels between post-war literatures of two divergent ‘lost’ generations.     

国有企业富余职工再就业探索

本文分析了国有企业富余职工存在的原因，指出政府在解决再就业问题上存在偏差。正确的指导思想应当是市场调节为主、经济效率优先。最后，作者提出了解决再就业问题的主要对策     

中西文化差异的经济观探析－兼论对我国文化体系变迁的影响

在21世纪,中西文化的差异和冲突将对我国的现代化建设产生极其深远的影响.本文从自然观、思维方式、文化心理、政治观念、外在形态等方面总结了中西方文化差异,着重从经济形态方面分析了中西文化差异产生的逻辑线索,概括总结了历史上在重建中国文化价值体系问题上的不同思潮并提出了作者的见解.     

Écrire la loi. Un travail de bureau pour hauts fonctionnaires du ministère de l’Écologie

This article analyses the process of the drafting of the Bachelot Bill on technological risks, passed on 30 July 2003 but initiated by Lionel Jospin's government immediately following the AZF factory disaster in September 2001. It focuses on the practical work of the civil servants at the Ministry of Ecology responsible for setting the orientations of the reform, transcribing them into legal provisions and ensuring that they would be supported and passed in Parliament. The analysis approaches the task by tracking both the successive versions of the bill and the multiple documents used in the preparation of these versions. This immersion in the administrative production of law provides a better understanding of the relations between the civil service and the political authorities, and shows how the boundary between these two worlds of practice is difficult to draw in the legal drafting process.