Data from the 1995 National Health Interview Survey (NHIS) indicate that, due to chronic conditions, the onset of activity limitation typically occurs between age 40-70 years (i.e., the proportion of young adults with activity limitation is small and roughly constant with age and then it starts to change, roughly increasing). We use a Bayesian hierarchical model to detect the change point of a positive activity limitation status (ALS) across twelve domains based on race, gender, and education. We have two types of data: weighted and unweighted. We obtain weighted binomial counts using a regression analysis with the sample weights. Given the proportion of individuals in the population with positive ALS, we assume that the number of individuals with positive ALS at each age group has a binomial probability mass function. The proportions across age are different, and have the same beta distribution up to the change point (unknown), and the proportions after the change point have a different beta distribution. We consider two different analyses. The first considers each domain individually in its own model and the second considers the twelve domains simultaneously in a single model to“borrow strength" as in small area estimation. It is reasonable to assume that each domain has its own onset.In the first analysis, we use the Gibbs sampler to fit the model, and a computation of the marginal likelihoods, using an output analysis from the Gibbs sampler, provides the posterior distribution of the change point. We note that a reversible jump sampler fails in this analysis because it tends to get stuck either age 40 or age 70. In the second analysis, we use the Gibbs sampler to fit only the joint posterior distribution of the twelve change points. This is a difficult problem because the joint density requires the numerical computation of a triple integral at each iteration. The other parameters of the process are obtained using data augmentation by a Metropolis sampler and a Rao-Blackwellization. We found that overall the age of onset is about 50 to 60 years.

This dissertation examined an implementation gap through a case study on implementing a District Health System (DHS) in the Western Cape Province of South Africa between October 2001 and April 2006. The research project explored why this implementation gap existed and what could be learnt about public policy implementation from studying this implementation gap. The main data collection methods included interviews, public and other documents and observations on the public health system in the Western Cape Province. I argue that implementation gaps could be interpreted as a signal of policy change instead of implementation failure. The key finding is that the Provincial Government of the Western Cape shifted its intentions regarding DHS implementation. The initial intention was to decentralise primary health care services to a metropolitan municipality. The decision, which was actively implemented, however centralised these services within the provincial government and started the process of the provincialisation of personal primary health care services in the Western Cape Province. This dissertation contributes to public policy implementation and public policy process literatures. It demonstrates why policy change is an alternative interpretation of implementation gaps to implementation failure and how policy change occurs during implementation. Policy change and public policy implementation are commonly two separate research themes within Public Policy Studies. The persuasion framework developed through this research project is an analytical tool that may be applied in research on implementation processes to examine whether an implementation gap is signalling policy change. The central theoretical elements in this framework that link policy change and implementation processes are the interactive effects of ideas and interests and the role of argument as a persuading factor that leads to policy change. The dissertation emphasises the role of language in public policy processes and argument and persuasion were deemed important elements in public policy processes.

En esta tesis se desarrolla una metodología estadística que permite obtener clasificaciones de modelos linalizables a través de una distancia basada en el concepto de información de Shamon. Se han obtenido explícitamente expresiones algebraicas de los estimadores que nos sirvieron para comparar dos o mas de dichas curvas estableciendo su relación con los contrastes de hipótesis propias del análisis de la varianza en el caso de que las curvas fueran asociadas a un modelo lineal normal de varianzas iguales. Finalmente, y como aplicación, se hace un análisis y una clasificación de distintos tipos de respuesta al TTOG en una muestra de niños, dando posteriormente un método de diagnostico automatizado que cuantifica sus errores.

This study presents the methodology for estimating the incidence rate from the age specific prevalence data of three different eye diseases. We consider both situations where the mortality may differ from one person to another, with and without the disease. The method used was developed by Marvin J. Podgor for estimating incidence rate from prevalence data. It delves into the application of logistic regression to obtain the smoothed prevalence rates that helps in obtaining incidence rate. The study concluded that the use of logistic regression can produce a meaningful model, and the incidence rates of these diseases were not affected by the assumption of differential mortality.

This dissertation seeks to incrementally explain the impact of individual, interpersonal, and environmental levels of risk upon HIV/STI incidents among heterosexual African American serodiscordant couples residing in four metropolitan cities. Using archival data from a cluster-RCT (Project EBAN) and governmental surveillance reports, analytic methods that can model heterogeneous pathways within and across each level of risk were used. Findings from this dissertation revealed unique patterns and pathways via which African American females in serodiscordant relationships contracted HIV/STI.

This thesis centres on the lives of women who live in Khayelitsha and who receive AIDS biomedicines through South Africa's public health system. It is tiered across five ethnographic chapters to elucidate a single overarching argument: biopolitical precarity is networked into the permeable body. This argument is based on ethnographic research and seeks to challenge the discursive construction of distance that divorces women's lives and bodies from the governance of AIDS biomedicines as life-­giving technologies. The multi-­sited ethnography underpinning this thesis was configured to follow the networked threads that weave women's embodied precarity into the governance of technologies and the technologies of governance. To this end, fieldwork was conducted in South Africa from October 2010 – July 2011 in order to understand the embodied and political dimensions of access to AIDS biomedicine. Thereafter, fieldwork was conducted in Brazil from August 2011 – September 2011 to explore the networked connections spanning activist organisations, government coalitions and economic blocs to move out from the intimate spaces of women's lives and bodies to locate them in the regional and global spaces of biomedical developments and health policy dynamics. This thesis argues that although it is crucial to anchor technologies in people's lives, it is also analytically and politically necessary to link people's lives - and the technologies that sustain them - back into the global assemblage that is networked around the governance of medicine. Therefore, I locate biomedical technologies in social and political contexts of lives of the people with whom I worked in Khayelitsha, and I argue further that their lives also need to be understood as part of a complex network of actors (spanning international organisations, regional coalitions and national governments) and actants (HIV and ARVs) that assemble in dynamic configurations and that are woven into and through the body.

Le travail de cette thèse s’interroge sur les réponses à apporter en terme d’organisation de l’offre médico-technique et de sa juste répartition sur les territoires en particulier pour les patients âgés poly-pathologiques. Il part de l’hypothèse qu’il existe un espace pour des concepts de petits établissements de santé ambulatoires pluridisciplinaires, dotés d’un petit plateau médico-technique, qui permettraient de participer à fluidifier et optimiser les parcours de soins. La méthode a consisté d’une part à étudier des structures plus petites de proximité en Allemagne, les MVZ, avec une expérience plus ancienne que celle dont nous disposons en France avec les MSP ou les Centres de Santé, et d’autre part à analyser les données PMSI pour faire émerger à la fois l’existence de groupes homogènes de co-morbidités et de groupes homogènes de parcours de soins. Les résultats sont constructifs, à la fois dans l’analyse par les sciences des réseaux et par l’automatisation de représentations de parcours de soins complexes. Ils ont permis de faire émerger des patterns représentatifs de groupes, d’en caractériser la consommation de soins, en matière de dispositifs médicaux et de ressources humaines, de quantifier les distances parcourues cumulées et les coûts cumulés par les patients selon leur lieu d’habitation et les institutions de santé auxquelles elles sont adressées. Nous en tirons des éléments pour la définition et la labellisation de nouvelles structures de santé de proximité satellites d’hôpitaux plus importants. Ce travail représente une avancée particulièrement utile, à la fois conceptuelle et pratique, pour les études de données de santé complexes des personnes âgées. / This work questions the answer to be given in terms of organization of the health technical offer and its fair distribution in the territories especially for the elderly patients with multimorbidities. It is based on the assumption that there is space for a concept of small multi-disciplinary outpatient health facilities, with a small health-technical platform, which would help to streamline and optimize care pathways. The method consisted on the one hand to study in Germany smaller community interdisciplinary health care center (the MVZ) in operation for a longer time than the the French multidisciplinary médical care centers. And on the other hand it analyzed the national heath data to reveal both the existence of comorbidités related groups and homogeneous care pathways related groups. The results are positive, both in network science analysis and in the automation of representations of complex care pathways. They made it possible to create representative patterns of groups, to characterize the consumption of care, in terms of medical devices and human resources, to quantify the cumulative distances traveled and the costs accumulated by patients according to their place of residence and the health institutions to which they are sent. We get addition elements for the definition and labeling of small community health centers, satellite of larger hospitals. This work represents a particularly useful step, both conceptual and practical, for complex health data studies of elderly.

Indiana University-Purdue University Indianapolis (IUPUI) / The anatomical sciences are experiencing a notable decrease in the time and resources devoted to embryology in North American medical education. With more changes assured, it is necessary to investigate the current trends in curriculum, pedagogy, and related experiences of embryology teachers and learners. To address these concerns, the researcher developed two online mixed methods surveys: one for current anatomy and embryology faculty and another for first year medical students. The faculty survey was followed by interviews with volunteers from that cohort. The researcher used a grounded theory methodology to analyze the qualitative components of the surveys, and descriptive statistics to analyze the quantitative components of the surveys. Both the faculty and student surveys illuminated the vast differences between the explicit, implicit, and null curricular components found in the numerous medical education programs represented. A combined grounded theory methodology and phenomenological approach was used to analyze the interviews with faculty. This generated a lived experience narrative of the phenomenon of teaching embryological content to medical students in the modern world, which led to a better understanding of the needs and challenges that face this subject matter and those who teach it. In this fluid era of medical education reform and integration, the perceptions and experiences of anatomy and embryology faculty and first year medical students are invaluable to assessing the curriculum and pedagogy of this foundational anatomical science and formulating evidence-based recommendations for the future.

Unexpected findings that contradict well-established relationships between exposures and outcomes are often referred to as “paradoxes” in the epidemiologic literature. For example, the “birth weight paradox” refers to the observed protective association between smoking during pregnancy and infant mortality among low birth weight infants. A recent body of literature suggests that this and several other well-known epidemiologic paradoxes can be attributed to collider bias. Collider bias results from conditioning on a variable that is caused by the exposure or shares common cause with the exposure and is caused by the outcome or shares common causes with the outcome. Several recent epidemiology textbooks and methodological studies further suggest that collider bias is the graphical representation of selection bias, suggesting that these two biases are synonymous. This structural approach to bias is conceptually very useful for defining, describing, and identifying selection bias, but it introduces paradoxes of its own due to contradictory conclusions in the selection and collider bias methodologic literatures about their likely impact on study results in terms of magnitude, direction, and strata affected. Resolving these discrepancies is essential for our theoretical understanding of the relationship between selection and collider bias and has important practical implications for how we teach epidemiology, design studies, and evaluate and quantify the potential effects of bias on our results. For example, while patterns of collider bias coincide qualitatively with the birth weight paradox, the magnitude of collider bias would have to be substantial to reverse the sign of the association, contrary to prevailing beliefs that collider bias only minimally affects our results. To date, the plausibility of collider bias as an explanation for the birth weight paradox has not been empirically evaluated using data in which the paradox is observed.Taken together, these inconsistencies and contradictions suggest that our understanding of selection bias and collider bias remains incomplete. The overarching goal of this dissertation was to advance the theoretical and quantitative understanding of the impact of collider bias on study results to clarify the relationship between selection and collider bias. I began by systematically reviewing the methodologic literature on selection and collider bias. I found that selection bias and collider bias are increasingly treated as synonyms, but that conclusions about the magnitude and direction of selection and collider bias, the stratum affected, and the conditions under which the effects of each type of bias were evaluated are highly inconsistent. This suggested that divergent findings about the impact of selection and collider bias might be resolved by considering the impact of collider bias under a broader set of circumstances. I used microsimulations grounded in the sufficient component cause model to examine collider bias not under the null; interrogate why multiplicative interaction appeared central to the impact of collider bias; and clarify which stratum or strata are affected by collider bias. I identified clear patterns for the magnitude, direction, and strata affected by collider bias and successfully reconciled discrepancies with the selection bias literature. This work also enabled me to interrogate both the causal mechanisms and mathematical principles that underlie collider bias, which revealed how collider bias leads to non-exchangeability and when stratifying on a collider results in bias. Finally, I applied this deeper understanding of the mechanisms underlying collider bias to empirically evaluate the plausibility of collider bias as an explanation for the birth weight paradox. Using microsimulations parameterized with 2015 National Center for Health Statistics Cohort Linked Birth-Infant Mortality, I identified scenarios that successfully reproduced the paradox and all observed relationships between smoking during pregnancy, infant mortality, and low birth weight. These findings strengthen the evidence for the role of collider bias in producing the paradox and shed light on the potential magnitude of unmeasured confounding and direct effects of smoking and low birth weight on infant mortality that may be required for the observed magnitude of the paradox to arise. This work clarifies that almost all selection bias is collider bias; that the effects of collider bias vary in magnitude and direction; that selecting on a collider always leads to bias, but this bias may not occur in the stratum that coincides with our analytical sample; and that collider bias may resolve the birth weight paradox, but is unlikely to explain all epidemiologic paradoxes.

The purpose of this research project is to report on a comprehensive organizational audit of the Urgent Care Service of Desert Valley Medical Group in Victorville, California.