Between a ROC and a hard place: Teaching prevalence plots to understand real world biomarker performance in the clinic

The Receiver Operating Characteristic (ROC) curve and the Area Under the Curve (AUC) of the ROC curve are widely used in discovery to compare the performance of diagnostic and prognostic assays. The ROC curve has the advantage that it is independent of disease prevalence. However, in this note, we remind scientists and clinicians that the performance of an assay upon translation to the clinic is critically dependent upon that very same prevalence. Without an understanding of prevalence in the test population, even robust bioassays with excellent ROC characteristics may perform poorly in the clinic. While the exact prevalence in the target population is not always known, simple plots of candidate assay performance as a function of prevalence rate give a better understanding of the likely real‐world performance and a greater understanding of the likely impact of variation in that prevalence on translation to the clinic.     

An Ecological Approach to Understanding Youth Violence: The Mediating Role of Substance Use

The authors tested an ecological model that posits mediating variables (substance use and mental health) in the association between ecological factors (family closeness, school closeness, and peer closeness) and youth violence in a sample of 4,783 adolescents. Model including substance use present significantly less total effect between ecological factors and youth violence than do models without substance use. Additional probing of significant mediation effect using the Sobel test was performed and suggested that substance use did function as a mediator in the hypothesized path. Considerations of adolescent violence should recognize the possible role of ecological factors and how their influence may vary by substance use.     

Data‐driven treatment selection for seamless phase II/III trials incorporating early‐outcome data

Seamless phase II/III clinical trials are conducted in two stages with treatment selection at the first stage. In the first stage, patients are randomized to a control or one of k > 1 experimental treatments. At the end of this stage, interim data are analysed, and a decision is made concerning which experimental treatment should continue to the second stage. If the primary endpoint is observable only after some period of follow‐up, at the interim analysis data may be available on some early outcome on a larger number of patients than those for whom the primary endpoint is available. These early endpoint data can thus be used for treatment selection. For two previously proposed approaches, the power has been shown to be greater for one or other method depending on the true treatment effects and correlations. We propose a new approach that builds on the previously proposed approaches and uses data available at the interim analysis to estimate these parameters and then, on the basis of these estimates, chooses the treatment selection method with the highest probability of correctly selecting the most effective treatment. This method is shown to perform well compared with the two previously described methods for a wide range of true parameter values. In most cases, the performance of the new method is either similar to or, in some cases, better than either of the two previously proposed methods. © 2014 The Authors. Pharmaceutical Statistics published by John Wiley & Sons Ltd.     

'ASK YOUR DOCTOR ABOUT...': DIRECT-TO-CONSUMER PRESCRIPTION DRUG ADVERTISING AND THE HIV/AIDS MEDICAL MARKETPLACE

This essay combines economic, historical and textual analysis to map the role of consumer-directed pharmaceutical advertising in the construction of the HIV/AIDS medical marketplace. In an apparent break from previous mainstream media representations that focused on HIV/AIDS as a ‘death sentence’, recent pharmaceutical advertising emphasizes the manageability of the syndrome by telling patients/consumers how they can live with HIV/AIDS. Historicizing the rise of direct-to-consumer drug advertising, the essay examines how this mode of consumerism might facilitate ‘political activism at the point of consumption’ (Nava, 1999).     

Of Art and Drudgery: Homekeeping,Martha Stewart,and Techné

Stewart’s voice is an exceptionally influential viewpoint in how we imagine and construct the twenty-first century North American home. In an era where more women than men attend college and where women make up a (slim) majority of the workforce, Stewart’s popularity is baffling to many. Locating Stewart within North American traditions of domestic advice, the author investigates how Stewart frames domestic arts as techné, arguing that Stewart’s profitability and popularity are so robust and wide-reaching because she rescues domestic arts from denigration, refiguring homekeeping as a techné of worth and importance. This article provides a framework for understanding the meaningful ways domesticity and design function as an ethics of daily life, problematizing the gendered dichotomy between production and consumption.     

Moment Inequalities and Their Application

This paper provides conditions under which the inequality constraints generated by either single agent optimizing behavior or the best response condition of multiple agent problems can be used as a basis for estimation and inference. An application illustrates how the use of these inequality constraints can simplify the analysis of complex behavioral models.     

Adult protective services clients confirmed for self-neglect: characteristics and service use

Self-neglect is a complex and inadequately understood phenomenon that accounts for the majority of Adult Protective Services cases. This retrospective, record-based study of the characteristics of 210 older adults who were reported to Adult Protective Services and confirmed for self-neglect revealed that common health problems included nutritional frailty, arthritis, and incontinence. Comparisons based upon length of service showed differences in worker-rated social environment risk, client capacity, and activities of daily living performance. Comparisons of findings with those of other studies of self-neglect underscore the need for systematic research on this population.     

Functional Assessment and Intervention for Organizational Behavior Change: Improving the Timeliness of Staff Meetings at a Human Services Organization

We implemented functional behavioral assessment (FBA) at a human services organization to reduce the tardiness of scheduled staff meetings. Following baseline, FBA focused on antecedent and consequence conditions that affected staff arriving on time to scheduled meetings. These data were subsequently presented at a staff meeting in which staff planned an intervention to improve the timeliness of meetings. The intervention, composed of premeeting reminders, positive reinforcement for arriving on time, and meeting termination criteria (to facilitate meeting-to-meeting transitions), was implemented in a multiple baseline design across 3 types of meetings. As a result of the intervention, the number of minutes late that meetings started decreased. We discuss FBA within organizational behavior management that targets performance improvement objectives.     

The pipeline: Botswana’s reception of refugees, 1956–68

This paper covers Botswana’s emergence as a place of refuge from its troubled white‐ruled neighbours. Botswana’s reception of refugees is seen as a symptom of, and as a catalyst for, its growing identification as a distinct nation in the region. From 1956, Bechuanaland colonial authorities distanced themselves from apartheid South Africa, and from 1957–58 the country received significant influxes of political refugees. The paper pays particular attention to the ‘pipeline’ that took refugees north across the Zambezi. This was initially protected from local police interference probably by Britain’s Secret Intelligence Service (MI6). Nelson Mandela, alias ‘David Motsamayi’, used the pipeline ‘down’ as well as ‘up’ to re‐enter South Africa. Such arrangements continued through independence in 1966 but were almost terminated when guerrilla fighters tried to use Botswana as a refuge in 1966–67. Revaluation of policy towards refugees within Botswana government circles resulted after 1969 in more overt moral support for liberation movements and, boosted by new economic strength, more self‐confident assertion of national sovereignty against neighbouring countries. This set the scene for Botswana to receive a huge influx of refugees as a result of the Soweto rising of 1976.