Optimising the trade-off between type I and II error rates in the Bayesian context

For any decision-making study, there are two sorts of errors that can be made, declaring a positive result when the truth is negative, and declaring a negative result when the truth is positive. Traditionally, the primary analysis of a study is a two-sided hypothesis test, the type I error rate will be set to 5% and the study is designed to give suitably low type II error – typically 10 or 20% – to detect a given effect size. These values are standard, arbitrary and, other than the choice between 10 and 20%, do not reflect the context of the study, such as the relative costs of making type I and II errors and the prior belief the drug will be placebo-like. Several authors have challenged this paradigm, typically for the scenario where the planned analysis is frequentist. When resource is limited, there will always be a trade-off between the type I and II error rates, and this article explores optimising this trade-off for a study with a planned Bayesian statistical analysis. This work provides a scientific basis for a discussion between stakeholders as to what type I and II error rates may be appropriate and some algebraic results for normally distributed data.     

Using Bayesian analysis in repeated preclinical in vivo studies for a more effective use of animals

Whilst innovative Bayesian approaches are increasingly used in clinical studies, in the preclinical area Bayesian methods appear to be rarely used in the reporting of pharmacology data. This is particularly surprising in the context of regularly repeated in vivo studies where there is a considerable amount of data from historical control groups, which has potential value. This paper describes our experience with introducing Bayesian analysis for such studies using a Bayesian meta‐analytic predictive approach. This leads naturally either to an informative prior for a control group as part of a full Bayesian analysis of the next study or using a predictive distribution to replace a control group entirely. We use quality control charts to illustrate study‐to‐study variation to the scientists and describe informative priors in terms of their approximate effective numbers of animals. We describe two case studies of animal models: the lipopolysaccharide‐induced cytokine release model used in inflammation and the novel object recognition model used to screen cognitive enhancers, both of which show the advantage of a Bayesian approach over the standard frequentist analysis. We conclude that using Bayesian methods in stable repeated in vivo studies can result in a more effective use of animals, either by reducing the total number of animals used or by increasing the precision of key treatment differences. This will lead to clearer results and supports the “3Rs initiative” to Refine, Reduce and Replace animals in research. Copyright © 2016 John Wiley & Sons, Ltd.     

Advantages of a wholly Bayesian approach to assessing efficacy in early drug development: a case study

This paper illustrates how the design and statistical analysis of the primary endpoint of a proof‐of‐concept study can be formulated within a Bayesian framework and is motivated by and illustrated with a Pfizer case study in chronic kidney disease. It is shown how decision criteria for success can be formulated, and how the study design can be assessed in relation to these, both using the traditional approach of probability of success conditional on the true treatment difference and also using Bayesian assurance and pre‐posterior probabilities. The case study illustrates how an informative prior on placebo response can have a dramatic effect in reducing sample size, saving time and resource, and we argue that in some cases, it can be considered unethical not to include relevant literature data in this way. Copyright © 2015 John Wiley & Sons, Ltd.     

HowParadigms Shape the Stories We Tell: Paradigm Shifts in Gender and Health

The stories we tell about the linkages between gender and health are shaped by the paradigms that guide our inquiries. Paradigms direct our attention away from certain phenomena and toward others. In particular, the dominant paradigms in the study of gender and health have promoted studies of differences, not similarities. Even in the face of strong challenges, many old paradigms persist. Continued reliance on flawed and insensitive paradigms is a major social issue. The aim of this article is to illustrate where we have come from, where we are now, and where we are heading in the study of gender and health. I will do this by tracking changes in the underlying paradigms that have shaped this research area, focusing on the literature in the area of gender and psychosocial factors, especially social-role experiences, and stress-related mental and physical health, to highlight changes that have taken place in these paradigms.     

Spatial heterogeneity in drinking water sources in the Greater Accra Metropolitan Area (GAMA), Ghana

Population and Environment - Universal access to safe drinking water is essential to population health and well-being, as recognized in the Sustainable Development Goals (SDG). To develop targeted...     

Reduced-hours careers in medicine: A strategy for the professional community and the family

This paper discusses the part-time professional career option, a career alternative thought to promote work-family integration, and asks whether this alternative would increase responsiveness to fluctuations in the demand for professionals. For illustrative purposes, we focus on the current oversupply of physicians in the United States, and discuss: (a) existing strategies to reduce this supply; (b) how current full-time schedules restrict professionals' ability to successfully combine work and family; and (c) the potential consequences of promoting part-time careers for the professional community and for families. Este papel describe la opcion de la carrera profesional tiempo medio, una carrera alternativa que se supone provee la integracion de trabajo y familia y hace la pregunta si esta alternativa aumentaria respuestas a altas y bajas en la demanda de profesionales. Para ilustrar, enfocamos en la actual sobre fuente de medicos en los Estados Unidos y discutimos: (a) estrategias existentes para reducir esta fuente; (b) como horarios de tiempo completo existentes resrictan a profesionales que equivale a la abilidad de positivamente combinar el trabajo y la familia; y (c) las consecuencias potenciales de promover carreras a tiempo medio para la comunidad profesional y sus familiares.     

Where Do Female Conservatives Stand? A Cross-National Analysis of the Issue Positions and Ideological Placement of Female Right-Wing Candidates

ABSTRACT

Many right-wing parties have attempted to increase their share of female representatives to appeal to women in the electorate. Underlying this is the assumption that women will offer a distinct perspective to the party. Using a comparative dataset of male and female candidates of Conservative and Christian Democratic parties across 21 European and Anglo-Saxon countries, we show this is the case. Female candidates in right-wing parties are less right wing than male candidates, both in terms of their overall ideology and their issue positioning. Perhaps as a consequence, female candidates perceive a greater distance to their own party than male candidates.     

Present and absent in troubling ways: families and social capital debates*

Social capital has become a key concept in Government policy‐making and academic circles. Particular forms of social capital theorising have become dominant and influential, invoking certain conceptions of the nature of family life. Inherently, ideas about ‘the family’ not only draw on gender divisions in fundamental ways, but also on particular forms of intergenerational relationships and power relations. This paper explores the place, and understandings, of family in social capital theorising from a feminist perspective, including the way that debates in the social capital field interlock with those in the family field. These encompass: posing both ‘the family’ and social capital as fundamental and strong bases for social cohesion, but also as easily eroded and in need of protection and encouragement; the relationship between ‘the private’ and ‘the social’; notions of bonding and bridging, and horizontal and vertical, forms of social capital as these relate to ideas about contemporary diversity in family forms and the nature of intimate relationships; and analytic approaches to understanding both the natures of social capital and family life in terms of an economic or moral rationality. It argues for greater reflexivity in the use of social capital as a concept, revealing rather than replicating troubling presences and absences around gender and generation as fundamental axes of family life.     

Family support: the roles of early years' centres

The development of children and the welfare of their parents are closely inter‐linked. The study outlined below uses a longitudinal, ecological approach to explore links between different models of early years' centres and the expansion of parents support networks. Over time, parenting stress reduced and well‐being improved. Sources of informal and formal support developed and extended. It is argued that all types of centres need to develop a comprehensive approach to child development in which child care and education, as well as family support, are explicit functions. This can promote family resilience as well as social inclusion in communities. Copyright © 2002 John Wiley & Sons, Ltd.     

A PATH TOWARD INTERRACIAL MARRIAGE: Women's First Partners and Husbands across Racial Lines

We examine interracial marriage as a culminating event in a sequence of intimate relationships across the life course. Using data from the 1995 National Survey of Family Growth, we analyze the background characteristics associated with selecting a first sex partner and first husband who differ in race/ethnicity from the respondent as well as the continuity across both outcomes. Our results show that respondents' race/ethnicity, parents' education, and region of birth are significant predictors of both choices. Selecting partners across racial lines for first sex is significantly associated with the selection of a first husband across race; the association between both outcomes is particularly strong for non-Hispanic black women, implying that social integration across race may be a life course phenomenon.