Missing data: Discussion points from the PSI missing data expert group

The Points to Consider Document on Missing Data was adopted by the Committee of Health and Medicinal Products (CHMP) in December 2001. In September 2007 the CHMP issued a recommendation to review the document, with particular emphasis on summarizing and critically appraising the pattern of drop‐outs, explaining the role and limitations of the ‘last observation carried forward’ method and describing the CHMP's cautionary stance on the use of mixed models. In preparation for the release of the updated guidance document, statisticians in the Pharmaceutical Industry held a one‐day expert group meeting in September 2008. Topics that were debated included minimizing the extent of missing data and understanding the missing data mechanism, defining the principles for handling missing data and understanding the assumptions underlying different analysis methods. A clear message from the meeting was that at present, biostatisticians tend only to react to missing data. Limited pro‐active planning is undertaken when designing clinical trials. Missing data mechanisms for a trial need to be considered during the planning phase and the impact on the objectives assessed. Another area for improvement is in the understanding of the pattern of missing data observed during a trial and thus the missing data mechanism via the plotting of data; for example, use of Kaplan–Meier curves looking at time to withdrawal. Copyright © 2009 John Wiley & Sons, Ltd.     

Similarity,Isomorphism or Duality? Recent Survey Evidence on the Human Resource Management Policies of Multinational Corporations

There is considerable debate as to the determinants of the human resource policies of human resource management: do they reflect national institutional or cultural realities, emerging common global practices, parent country effects or the dual effects of transnational and national realities? We use an extensive international database to explore these differences, assessing variations in a range of human resource practices. We find new evidence of national differences in the manner in which indigenous firms manage their people, but also evidence of a similarity in practice amongst multinational corporations. In other words, multinational corporations tend to manage their human resources in ways that are distinct from those of their host country; at the same time, country of origin effects seem relatively weak. Whilst there is some evidence of common global practices, sufficient diversity in practice persists to suggest that duality theories may provide the most appropriate explanation.     

Conditional approval: discussion points from the PSI conditional approval expert group

The European Agency for the Evaluation of Medicinal Products has recently completed the consultation of a draft guidance on how to implement conditional approval. This route of application is available for orphan drugs, emergency situations and serious debilitating or life-threatening diseases. Although there has been limited experience in implementing conditional approval to date, PSI (Statisticians in the Pharmaceutical Industry) sponsored a meeting of pharmaceutical statisticians with an interest in the area to discuss potential issues. This article outlines the issues raised and resulting discussions, based on the group's interpretation of the legislation. Conditional approval seems to fit well with the accepted regulatory strategy in HIV. In oncology, conditional approval may be most likely when (a) compelling phase II data are available using accepted clinical outcomes (e.g. progression/recurrence-free survival or overall survival) and Phase III has been planned or started, or (b) when data are available using a surrogate endpoint for clinical outcome (e.g. response rate or biochemical measures) from a single-arm study in rare tumours with high response, compared with historical data. The use of interim analyses in Phase III for supporting conditional approval raises some challenging issues regarding dissemination of information, maintenance of blinding, potential introduction of bias, ethics, switching, etc.     

Disparities in Educational Opportunities and Outcomes: What Do We Know and What Can We Do?

This article examines disparities based upon poverty and race/ethnicity. After framing the issues by looking at national, state, and local data, it illustrates ways that social scientists can be involved in shaping educational practices and policies, focusing on the types of skills that are useful and on ways of thinking about the types of collaboration that are needed. Skills discussed are methodological as well as substantive; both types draw from existing knowledge bases. For collaboration, the model described is that of action research. Approaches are illustrated through personal examples drawn from collaborations with urban public schools. They include defining expected growth for students at different achievement levels, school accountability issues, and setting up long-term collaboration .     

Multi-Organizational Fields and Social Movement Organization Frame Content: The Religious Fro-Choice Movement*

As an explanatory method in studies of social movements, analyses of collective action frames have generally focused on the variable efficacy of the frames of social movement organizations (SMOs)in the mobilization of potential participants. However, this work has for practical reasons used the acknowledged analytic simplification that SMOs only target potential participants–and not opponents, elite decision makers, or the media–when constructing their frames. To incorporate multiple targets into future studies of SMO frame construction, this paper expands on the idea of a multi-organizational field. I propose that the characteristics of the targets in the field and the social structural and cognitive boundaries between them determine SMO frames. This perspective is demonstrated by analyzing changes in the collective action frames of SMOs in the religious pro-choice movement from 1967 to 1992. I argue that this perspective may explain findings where a frame fails to “resonate” with potential participants–the frame may not have been created with them in mind.     

Talking about money: public participation and expert knowledge in the Euro referendum

This paper uses the proposed UK referendum on the single European currency as a means of investigating the effect of democratizing science on the scrutiny of conflicting expert advice. Although the referendum has not happened yet, and may not happen at all, the campaigners for and against the Euro have none the less been working for several years to ensure that if, and when, it does happen they are in a position to win it. By exploring how campaigners on both sides of the debate understand the concerns of voters, the paper shows how they are working towards a referendum in which the political dimensions of the Euro are actively minimized in order to avoid alienating key 'floating voters'. Instead, the campaign is expected to focus on the economic costs and benefits of the Euro for individuals and households, with only limited discussion of issues relating to sovereignty. Whether or not the campaign groups, particularly those that oppose the Euro, can maintain this line remains to be seen but if there is a full and frank public debate about the economic, social and political stakes, then this will be despite the referendum rather than because of it.     

Rural and urban women's perceptions of barriers to health, mental health, and criminal justice services: implications for victim services

The purpose of this study was to examine rural and urban women's perceptions of barriers to health and mental health services as well as barriers to criminal justice system services. Eight focus groups were conducted, two in a selected urban county (n = 30 women) and two in each of three selected rural counties (n = 98 women). Results were classified into a barrier framework developed in the health service utilization literature which suggests there are four main dimensions of barriers: affordability, availability, accessibility, and acceptability. Results indicate that: (1) women face many barriers to service use including affordability, availability, accessibility, and acceptability barriers; (2) it takes an inordinate level of effort to obtain all kinds of services; however, women with victimization histories may face additional barriers over and above women without victimization histories; (3) barriers to health and mental health service utilization overlap with barriers to utilizing the criminal justice system; and (4) there are many similarities in barriers to service use among rural and urban women; however, there are some important differences suggesting barriers are contextual. Future research is needed to further clarify barriers to service use for women with victimization histories in general, and specifically for rural and urban women. In addition, future research is needed to better understand how women cope with victimization in the context of the specific barriers they face in their communities.