Estimation in the Cox cure model with covariates missing not at random,with application to disease screening/prediction

In an attempt to provide a statistical tool for disease screening and prediction, we propose a semiparametric approach to analysis of the Cox proportional hazards cure model in situations where the observations on the event time are subject to right censoring and some covariates are missing not at random. To facilitate the methodological development, we begin with semiparametric maximum likelihood estimation (SPMLE) assuming that the (conditional) distribution of the missing covariates is known. A variant of the EM algorithm is used to compute the estimator. We then adapt the SPMLE to a more practical situation where the distribution is unknown and there is a consistent estimator based on available information. We establish the consistency and weak convergence of the resulting pseudo-SPMLE, and identify a suitable variance estimator. The application of our inference procedure to disease screening and prediction is illustrated via empirical studies. The proposed approach is used to analyze the tuberculosis screening study data that motivated this research. Its finite-sample performance is examined by simulation.     

Seed funding for health promotion: sowing sustainability or skepticism?

Health promotion activities are enjoying renewed attention fromgovernments under the rubric of chronic disease prevention,yet often with similar and inadequate resources. Seed-fundingopportunities are popular means for governments to distributemonies and groom communities to embed the funded activitiesinto local ecology. The success of seed funding in nurturingcommunity capacity and engendering program sustainability iscontroversial. This article discusses a recent seed-fundingexperience in the Canadian province of British Columbia.     

Deconstructing disproportionality: views from multiple community stakeholders

While the existence of racial disproportionality has been well documented, the causes of disproportionality are less clear. Studies identifying contributing factors have relied largely on analyses of state and national data sets, which may lack the robust data necessary to fully explain the factors related to this issue. Further, a limitation of existing research is the lack of data from the voice of those in communities affected by disproportionality. This study was designed to develop a deeper understanding of disproportionality from the views of multiple community stakeholders. Using a qualitative approach, data were collected to provide a greater depth of information that can be used alongside existing studies toward developing an enhanced understanding of disproportionality in child welfare.     

Grave fraudulence in medical device research: a narrative review of the PIN seeding study for the Pinnacle hip system

In 2001, DePuy, a wholly-owned subsidiary of Johnson & Johnson (J&J/DePuy), initiated a seeding study called the “Multi-center, Prospective, Clinical Evaluation of Pinnacle Acetabular Implants in Total Hip Arthroplasty” (PIN Study). J&J/DePuy designed this study to develop new business opportunities during the launch of their Pinnacle Hip System (PHS) and generate survivorship data for marketing. This article, the first review of a seeding trial for a medical device, examines internal company documents relating to the PIN Study; the analysis herein focuses on the integrity of J&J/DePuy’s research practices in conception, implementation, and analysis. J&J/DePuy violated the study protocol and manipulated data; consented participants in violation of standards protecting human subjects; and did not secure Institutional Review Board approval for all study sites. J&J/DePuy used PIN Study results as the “fundamental selling point” for the PHS. Medical device seeding trials are distinct from previously-documented pharmaceutical seeding trials because companies can profit directly from device sales and because these studies may be the first clinical evaluation of the device (as was the case for the PIN Study). Seeding trials are malleable marketing projects, not rigorous scientific studies. Regulatory bodies, physicians, and others should be vigilant for persuasive marketing accounts disguised as science.     

Explaining Optimistic Old Age Disability and Longevity Expectations

Biased health care decision making has been regarded as responsible for inefficient behaviours (for example, the limited insurance purchase). This paper empirically examines two sets of biases in the perception of old age disability and longevity. Particularly, we test for the existence of a so called cumulative bias and, secondly’ a so called optimism’ bias. Findings are suggestive of a significant overestimation of disability risks but no overestimation of longevity expectations is found. Both disability and longevity perceptions appear to exhibit a ‘cumulative’ pattern when mapped over time. Healthier individuals are less likely to perceive high disability and longevity risks whilst female and younger respondents perceive a higher risk of disability in old age at a population level but not at an individual level.     

Gender differences in labor market wages: A comparison of industrial sector effects and a decomposition within four occupations

Women earn less than men. The reason may be due to either industrial segmentation or occupational segregation or both according to the current research. Researches focusing on one structure tend to neglect the other or to use an inadequate representation. This article examines the simultaneous impact of industrial sector and gender on imputed wages with labor force incumbents in four detailed occupations. These occupations are from a set identified as relatively internally homogeneous on measures of task performed from the Dictionary of Occupational Titles. Thus, within-occupational differences in work performed between males and females are minimized. The findings reinforce the importance of industrial sector for economic outcomes and demonstrate the value of an improved representation of occupation. The decomposition shows wage discrimination exists against females in each of these occupations, and in two sector-by-sector occupation comparisons, females should earn more than males.     

Public Perceptions of Health Risks from Polluted Coastal Bathing Waters: A Mixed Methodological Analysis Using Cultural Theory

This article explores public perceptions of, and attitudes toward, possible health risks from polluted coastal bathing waters in the United Kingdom. Cultural theory is applied in the present analysis, using a mixed methodology of quantitative analysis from interviews and qualitative interpretation of focus group discussions to provide insights into how different cultural solidarities view a number of issues. These include risks to health; attitudes toward regulation; public consultation and information provision; and trust, blame, and accountability applied to different stakeholders in the bathing-water-quality debate. The results show that individuals' standpoints can be represented on a number of dimensions, consistent with cultural theory, including perceptions of power and authority, beliefs in the efficacy of collective action, and acceptance or rejection of incremental change as opposed to radical solutions. The discussion focuses both on methodological and substantive issues related to the use of cultural theory as a research tool, and on policy recommendations arising from this research.     

What's So Special? Teachers' Models and Their Realisation in Practice in Segregated Schools

The concept of 'special' has played a crucial role in the development of educational policy and practice, and the meaning of the term has been the subject of far-reaching debates and controversy. This paper is based on research which explored the meaning of 'specialness' in theory and practice from the point of view of practitioners working in segregated schools, providing education for young people designated as having moderate and severe learning difficulties. The research demonstrates the articulation of the individual model of special in teachers' thinking about pupils, themselves and their relationships with pupils, and also in the learning environment provided for different categories of young people. We argue that the dominant discursive practices of practitioners construct and maintain 'otherness' in special education, and pre-empt alternative discourses.     

Towards next-generation visual archives: image,film and discourse

The digital turn in visual studies has played a major role in the terminological overlap between ‘archive’, ‘database’ and ‘corpus’, and it has brought about a number of positive developments such as improved accessibility and availability. At the same time, it has also raised important questions pertaining to the materiality, searchability, annotation and analysis of the data at hand. Through a series of theoretical constructs and empirical examples, this paper illustrates the necessity and benefits of interdisciplinary dialogue when tackling the multimodal corpus annotation challenge. The meaningful interrelations between semiotic modes, the combinations between manual and (semi)automated annotation, the seamless integration of coding and annotation schemes which share common logics and the contextual embedding of the presented analyses strongly suggest multimodal document analysis in all its forms will continuously benefit from a corpus-based approach.