Limitations to Empirical Extrapolation Studies: The Case of BMD Ratios

Extrapolation relationships are of keen interest to chemical risk assessment in which they play a prominent role in translating experimentally derived (usually in animals) toxicity estimates into estimates more relevant to human populations. A standard approach for characterizing each extrapolation relies on ratios of pre-existing toxicity estimates. Applications of this "ratio approach" have overlooked several sources of error. This article examines the case of ratios of benchmark doses, trying to better understand their informativeness. The approach involves mathematically modeling the process by which the ratios are generated in practice. Both closed form and simulation-based models of this "data-generating process" (DGP) are developed, paying special attention to the influence of experimental design. The results show the potential for significant limits to informativeness, and revealing dependencies. Future applications of the ratio approach should take imprecision and bias into account. Bootstrap techniques are recommended for gauging imprecision, but more complicated techniques will be required for gauging bias (and capturing dependencies). Strategies for mitigating the errors are suggested.     

Risk-Based Environmental Remediation: Bayesian Monte Carlo Analysis and the Expected Value of Sample Information

A methodology that simulates outcomes from future data collection programs, utilizes Bayesian Monte Carlo analysis to predict the resulting reduction in uncertainty in an environmental fate-and-transport model, and estimates the expected value of this reduction in uncertainty to a risk-based environmental remediation decision is illustrated considering polychlorinated biphenyl (PCB) sediment contamination and uptake by winter flounder in New Bedford Harbor, MA. The expected value of sample information (EVSI), the difference between the expected loss of the optimal decision based on the prior uncertainty analysis and the expected loss of the optimal decision from an updated information state, is calculated for several sampling plan. For the illustrative application we have posed, the EVSI for a sampling plan of two data points is $9.4 million, for five data points is $10.4 million, and for ten data points is $11.5 million. The EVSI for sampling plans involving larger numbers of data points is bounded by the expected value of perfect information, $15.6 million. A sensitivity analysis is conducted to examine the effect of selected model structure and parametric assumptions on the optimal decision and the EVSI. The optimal decision (total area to be dredged) is sensitive to the assumption of linearity between PCB sediment concentration and flounder PCB body burden and to the assumed relationship between area dredged and the harbor-wide average sediment PCB concentration; these assumptions also have a moderate impact on the computed EVSI. The EVSI is most sensitive to the unit cost of remediation and rather insensitive to the penalty cost associated with under-remediation.     

Residential Radon in Canada: An Uncertainty Analysis of Population and Individual Lung Cancer Risk

Following a comprehensive evaluation of the health risks of radon, the U.S. National Research Council (US-NRC) concluded that the radon inside the homes of U.S. residents is an important cause of lung cancer. To assess lung cancer risks associated with radon exposure in Canadian homes, we apply the new (US-NRC) techniques, tailoring assumptions to the Canadian context. A two-dimensional uncertainty analysis is used to provide both population-based (population attributable risk, PAR; excess lifetime risk ratio, ELRR; and life-years lost, LYL) and individual-based (ELRR and LYL) estimates. Our primary results obtained for the Canadian population reveal mean estimates for ELRR, PAR, and LYL are 0.08, 8%, and 0.10 years, respectively. Results are also available and stratified by smoking status (ever versus never). Conveniently, the three indices (ELRR, PAR, and LYL) reveal similar output uncertainty (geometric standard deviation, GSD approximately 1.3), and in the case of ELRR and LYL, comparable variability and uncertainty combined (GSD approximately 4.2). Simplifying relationships are identified between ELRR, LYL, PAR, and the age-specific excess rate ratio (ERR), which suggest a way to scale results from one population to another. This insight is applied in scaling our baseline results to obtain gender-specific estimates, as well as in simplifying and illuminating sensitivity analysis.     

Social Workers’ Preparation for Child Protection: Revisiting the Question of Specialisation

Abstract

Child welfare work is a key field of practice for social work graduates and for graduates of a growing range of disciplines. In the present paper, the authors drew on a survey of 208 child welfare workers and interviews with 28 senior personnel in child and family welfare agencies to analyse perceptions of the educational preparation of social workers and other human science graduates for this field of practice. The findings indicated that child welfare workers and employers are ambivalent about the value of social work and other generic social science and human services programmes as preparation for tertiary or statutory child protection practice, which involves investigation, assessment, and intervention in child abuse and neglect. The authors argue that the social work profession must better balance generic and specialist aspects to prepare graduates for practice in specialist fields of high social work involvement, particularly in tertiary child protection work.     

Efficacy of Co-Parenting for Successful Kids: A Longitudinal Pilot Investigation

ABSTRACT

With a sample of 155 divorcing parents, this study examined the efficacy of a co-parenting program titled Co-Parenting for Successful Kids (CPSK). A prospective longitudinal cohort study was used to assess parental outcomes at multiple time points (i.e., pre-test, post-test, and three-month follow-up). Using validated scales, we measured parenting stress, parenting self-efficacy, and parental anger over time. The results indicated that the participants experienced reduced parenting stress and parental anger, and increased parenting self-efficacy after completion of the co-parenting program. Co-parenting interventions to help divorcing parents with stress management, and continuously work together collaboratively in raising their children should be encouraged.     

It takes a team: Improving placement stability among children and youth with Fetal Alcohol Spectrum Disorder in care in Canada

Concerted efforts have been devoted to improving placement stability for children in care. These efforts have been driven by evidence of negative outcomes for foster children who experience frequent placement changes. Of particular concern are significantly higher rates of placement disruptions among children in care who experience Fetal Alcohol Spectrum Disorder (FASD). This mixed methods study examines the impact of enhanced child welfare practice interventions on placement stability for 182 children in care who experience FASD. A quasi-experimental matched comparison group design was employed, where rates of placement change were compared between children in the Project Regions who received enhanced practice standards to those in the Comparison Regions who did not. The sample included 182 participants including 98 children and youth in care from the Project Region and 84 cases from the Comparison Region. The Project Regions reported considerably lower placement changes (M = .33) than the Comparison Region (M = .98). Logistic regression analysis revealed that worker contact was found to be predictive of placement stability. Specifically, as worker contact increased, the likelihood of placement change decreased [B = − .28, W (5.35, p = .02)]. In keeping with the adage that it takes a village to raise a child, one could add for children affected by FASD, that it takes a dedicated team to promote placement stability and better life trajectories.     

The Changing Shape Of Pregnancy In New Zealand Women's Magazines: 1970–2008

This article examines the representation of pregnant embodiment in thirteen New Zealand women's magazines published between January 1970 and December 2008. It offers a theoretical focus on postfeminism, media, and embodiment, and situates their conjuncture within cultural, demographic, and labour market trends. Magazine representations of pregnancy concurrently illustrate the degree to which discourses surrounding pregnancy have shifted, and the continued association of motherhood with feminine success. Monthly and weekly publications were sampled and a visual analysis undertaken of images and spreads. Over nearly four decades, substantial changes were found in the normative or extraordinary status of pregnancy, the appearance and display of the pregnant body, the frequency of representations, the association of pregnancy with celebrity, and its dissemination through celebrity culture. Changes in the status of pregnancy parallel larger social changes, in particular the increase in delayed childbearing amongst white, middle-class women. Pregnancy images were also influenced by changes in the format and substance of women's magazines, the advent of celebrity culture, and the emergence of a maternity market.     

See no evil,hear no evil,speak no evil: assessing complex trauma in young children

Complex trauma generally refers to a child's exposure to multiple traumatic events often within the context of an interpersonal relationship. Childhood traumatic events are commonplace and can have significant implications for physical and mental health. However, traumatic events are often not assessed by clinicians involved in their care. This paper outlines an approach to assessing complex trauma in young children in clinical settings. This approach involves an initial interview, an assessment of traumatic events and trauma symptoms in the child, an assessment of the parent–child interaction, an understanding of the child's functioning in multiple settings, and an assessment of parental trauma where relevant. Complex trauma takes time to assess and is dependent on the parent's ability to recognise and acknowledge the effect trauma has had. The paper concludes with some of the challenges when assessing complex trauma in young children in clinical settings.     

‘Contestation,negotiation, and resolution’: The relationship between power and collective leadership

The relationship between power and collective leadership (CL) has been theoretically understood and empirically addressed in many different ways. To make sense of this diversity, we investigate and diagram the role of power in CL. First, we identify six representations of power—six ways in which scholars have found that power shapes the emergence and enactment of CL. These representations include: Even in CL, individual power matters; Leaders can devolve power to their subordinates by empowering them; Contextual characteristics related to power can influence the possibility and enactment of CL; CL can create the collective power necessary for people in marginalized positions to challenge embedded power dynamics; Power is intrinsic to the co-construction process; Attributions affect who can enact CL, how they are viewed, and whether they have power. Second, we offer a conceptual framework that provides a comprehensive way to understand the relationship between power and CL. The framework includes two dimensions, one related to power (that runs from episodic to systemic) and the other related to CL (that runs from entitative to emergent). Third, we create a conceptual map by placing the six representations within this framework. Based on our research, we make the case that we cannot understand CL without understanding the ubiquitous, complex, and even contradictory role of power. We also suggest avenues for expanding and elaborating discussions of power in the CL literature.     

Racial Attitudes in the Deep South: Persistence and Change at the University of Alabama, 1963–2013*

Using data from a unique series of surveys collected between 1963 and 2013, this study examines racial attitudes among young white adults in the Deep South over a 50-year period. Repeated surveys of University of Alabama students in 1963, 1966, 1969, 1972, 1983, 1988, and 2013 measured racial stereotypes, support for racial segregation, and in the 2013 study, racial resentment and support for ameliorative racial policies. Analyses show that in the 1960s endorsement of racial stereotypes was a powerful predictor of support for racial segregation. By the early 1970s, racial integration became a reality in the Deep South and, paralleling broad trends in U.S. society, endorsement of racial stereotypes and support for racial segregation declined. Simultaneously, threats to whites' position in the form of ameliorative racial policies (including affirmative action) emerged along with racial resentment. By 2013, racial resentment, rather than racial stereotyping, was the primary determinant of white students' opposition to racial change. Our findings support Herbert Blumer's (1958) argument that racial prejudice exists in a sense of group position, and that it functions to preserve the advantaged position of the dominant group regardless of changes in the form that prejudice takes.