Tame combing and almost convexity conditions

We give the first examples of groups which admit a tame combing with linear radial tameness function with respect to any choice of finite presentation, but which are not minimally almost convex on a standard generating set. Namely, we explicitly construct such combings for Thompson's group F and the Baumslag-Solitar groups BS(1, p) with p \ge 3. In order to make this construction for Thompson's group F, we significantly expand the understanding of the Cayley complex of this group with respect to the standard finite presentation. In particular we describe a quasigeodesic set of normal forms and combinatorially classify the arrangements of 2-cells adjacent to edges that do not lie on normal form paths.Comment: 36 pages, 9 figure

Setting priorities in health research using the model proposed by the World Health Organization: development of a quantitative methodology using tuberculosis in South Africa as a worked example

BackgroundSetting priorities is important in health research given the limited resources available for research. Various guidelines exist to assist in the priority setting process; however, priority setting still faces significant challenges such as the clear ranking of identified priorities. The World Health Organization (WHO) proposed a Disability Adjusted Life Year (DALY)-based model to rank priorities by research area (basic, health systems and biomedical) by dividing the DALYs into ‘unavertable with existing interventions’, ‘avertable with improved efficiency’ and ‘avertable with existing but non-cost-effective interventions’, respectively. However, the model has conceptual flaws and no clear methodology for its construction. Therefore, the aim of this paper was to amend the model to address these flaws, and develop a clear methodology by using tuberculosis in South Africa as a worked example.MethodsAn amended model was constructed to represent total DALYs as the product of DALYs per person and absolute burden of disease. These figures were calculated for all countries from WHO datasets. The lowest figures achieved by any country were assumed to represent ‘unavertable with existing interventions’ if extrapolated to South Africa. The ratio of ‘cost per patient treated’ (adjusted for purchasing power and outcome weighted) between South Africa and the best country was used to calculate the ‘avertable with improved efficiency section’. Finally, ‘avertable with existing but non-cost-effective interventions’ was calculated using Disease Control Priorities Project efficacy data, and the ratio between the best intervention and South Africa’s current intervention, irrespective of cost.ResultsThe amended model shows that South Africa has a tuberculosis burden of 1,009,837.3 DALYs; 0.009% of DALYs are unavertable with existing interventions and 96.3% of DALYs could be averted with improvements in efficiency. Of the remaining DALYs, a further 56.9% could be averted with existing but non-cost-effective interventions.ConclusionsThe amended model was successfully constructed using limited data sources. The generalizability of the data used is the main limitation of the model. More complex formulas are required to deal with such potential confounding variables; however, the results act as starting point for development of a more robust model.Electronic supplementary materialThe online version of this article (doi:10.1186/s12961-016-0081-8) contains supplementary material, which is available to authorized users

Equity and efficiency in health and health care for HIV-positive adults in South Africa

Includes bibliographical references (leaves 238-258).This dissertation presents a framework for assessing equity and efficiency in health and health care for HIV-positive adults in South Africa, which is tested in the extensive analysis of empirical data on the costs and consequences of alternative HIV-treatment strategies in the public health care system. The framework is built through asking three key questions. The first question -- what is the good (value or benefit) of health care -- considers what ought to be in the evaluative space of distributive justice in relation to this dissertation and in health economics more generally. The second question considers the factors that might constitute claims on this good, including personal responsibility, need, the social context as well as the impact of allocations of the good on the health of society and the social fabric. The final question -- how should the good be distributed -- examines alternative social choice rules for distributing the good and develops an approach grounded in procedural justice that legitimizes the choice of one rule over another. To apply this framework, patient and population-level costs and consequences associated with alternative HIV-treatment interventions are analysed in Markov models. These are extensively validated and uncertainty is assessed through probabilistic and multi-way sensitivity analyses. Results of these analyses are key inputs into mathematical programming algorithms that allow an assessment of the implications of choosing one social choice rule over another in terms of gains in the good and the proportion of need that can be met through one or more treatment strategy across a range of budgets. In discussing and concluding, these empirical results are reintegrated into the conceptual framework where the notion of claims on the good and a decision-making approach grounded in procedural justice is further developed. It is argued that the proper implementation of this framework will result in allocations of the good that are fair even if this is at a level of less than universal access to the most effective treatment strategy

Assessing the Impact of Family Status, Family Cohesion, and Acculturation on Youth Violence Among Immigrant Latinos

Background/Objectives: Latino youth violence is an emerging public health concern. The objective is to assess the impact of family status, family cohesion, and acculturation on youth violence among Latino immigrants in Langley Park, MD compared with a control community in Culmore, VA. Methods: Constructs were generated from survey questions to represent family support and cohesion, acculturation, and youth violence. Bivariate and multivariate regression analyses were modeled to evaluate the relationships between family support and cohesion, acculturation, and violence, after adjusting for confounders. Results: After controlling for covariates, family support consistently reduced victimization (PE = ‐0.02, SE = 0.01, t = ‐2.64, p‐value = 0.0085); increased non‐violence attitudes and beliefs (PE = 0.32, SE = 0.05, t = 6.17, p‐value = Conclusions: Family support is associated with reduced violence engagement and risk behaviors among Latino youth. Results will inform the development and implementation of future youth violence prevention programs among ethnic minorities and immigrants

Factors associated with patterns of plural healthcare utilization among patients taking antiretroviral therapy in rural and urban South Africa: a cross sectional study

Background: In low-resource settings, patients’ use of multiple healthcare sources may complicate chronic care and clinical outcomes as antiretroviral therapy (ART) continues to expand. However, little is known regarding patterns, drivers and consequences of using multiple healthcare sources. We therefore investigated factors associated with patterns of plural healthcare usage among patients taking ART in diverse South African settings. Methods: A cross-sectional study of patients taking ART was conducted in two rural and two urban sub-districts, involving 13 accredited facilities and 1266 participants selected through systematic random sampling. Structured questionnaires were used in interviews, and participant’s clinic records were reviewed. Data collected included household assets, healthcare access dimensions (availability, affordability and acceptability), healthcare utilization and pluralism, and laboratory-based outcomes. Multiple logistic regression models were fitted to identify predictors of healthcare pluralism and associations with treatment outcomes. Prior ethical approval and informed consent were obtained. Results: Nineteen percent of respondents reported use of additional healthcare providers over and above their regular ART visits in the prior month. A further 15% of respondents reported additional expenditure on self-care (e.g. special foods). Access to health insurance (Adjusted odds ratio [aOR] 6.15) and disability grants (aOR 1.35) increased plural healthcare use. However, plural healthcare users were more likely to borrow money to finance healthcare (aOR 2.68), and incur catastrophic levels of healthcare expenditure (27%) than non-plural users (7%). Quality of care factors, such as perceived disrespect by staff (aOR 2.07) and lack of privacy (aOR 1.50) increased plural healthcare utilization. Plural healthcare utilization was associated with rural residence (aOR 1.97). Healthcare pluralism was not associated with missed visits or biological outcomes. Conclusion: Increased plural healthcare utilization, inequitably distributed between rural and urban areas, is largely a function of higher socioeconomic status, better ability to finance healthcare and factors related to poor quality of care in ART clinics. Plural healthcare utilization may be an indication of patients’ dissatisfaction with perceived quality of ART care provided. Healthcare expenditure of a catastrophic nature remained a persistent complication. Plural healthcare utilization did not appear to influence clinical outcomes. However, there were potential negative impacts on the livelihoods of patients and their households.Web of Scienc

The cost-effectiveness of Antiretroviral Treatment in Khayelitsha, South Africa – a primary data analysis

BACKGROUND: Given the size of the HIV epidemic in South Africa and other developing countries, scaling up antiretroviral treatment (ART) represents one of the key public health challenges of the next decade. Appropriate priority setting and budgeting can be assisted by economic data on the costs and cost-effectiveness of ART. The objectives of this research were therefore to estimate HIV healthcare utilisation, the unit costs of HIV services and the cost per life year (LY) and quality adjusted life year (QALY) gained of HIV treatment interventions from a provider's perspective. METHODS: Data on service utilisation, outcomes and costs were collected in the Western Cape Province of South Africa. Utilisation of a full range of HIV healthcare services was estimated from 1,729 patients in the Khayelitsha cohort (1,146 No-ART patient-years, 2,229 ART patient-years) using a before and after study design. Full economic costs of HIV-related services were calculated and were complemented by appropriate secondary data. ART effects (deaths, therapy discontinuation and switching to second-line) were from the same 1,729 patients followed for a maximum of 4 years on ART. No-ART outcomes were estimated from a local natural history cohort. Health-related quality of life was assessed on a sub-sample of 95 patients. Markov modelling was used to calculate lifetime costs, LYs and QALYs and uncertainty was assessed through probabilistic sensitivity analysis on all utilisation and outcome variables. An alternative scenario was constructed to enhance generalizability. RESULTS: Discounted lifetime costs for No-ART and ART were US$2,743 and US$9,435 over 2 and 8 QALYs respectively. The incremental cost-effectiveness ratio through the use of ART versus No-ART was US$1,102 (95$984 (95% CI 913-1,078) per life year gained. In an alternative scenario where adjustments were made across cost, outcome and utilisation parameters, costs and outcomes were lower, but the ICER was similar. CONCLUSION: Decisions to scale-up ART across sub-Saharan Africa have been made in the absence of incremental lifetime cost and cost-effectiveness data which seriously limits attempts to secure funds at the global level for HIV treatment or to set priorities at the country level. This article presents baseline cost-effectiveness data from one of the longest running public healthcare antiretroviral treatment programmes in Africa that could assist in enhancing efficient resource allocation and equitable access to HIV treatment

The How and Why of the New Public Corporation Tax Shelter Compliance Norm

This paper examines the recent shift toward an anti-tax shelter federal income tax compliance norm at public corporations, as evidenced by practitioner and government comments and survey results. The paper focuses on the organizational behavior of tax decisionmakers within public corporations as they respond to Sarbanes-Oxley, enforcement and publicity initiatives, and tax shelter regulation. The paper identifies three elements that have contributed to the development of a stronger tax compliance norm. First, Sarbanes-Oxley has resulted in the expansion and increased transparency of public corporation tax decisionmaking groups. Organizational behavior insights suggest that this may produce more considered decisions. Second, civil and criminal enforcement and accompanying publicity have resulted in real concerns about personal and firm liability among organization leaders. This causes organization hierarchies to encourage and reward compliance. Third, the government has clearly identified objectionable tax shelter transactions and plainly labeled them unacceptable and even fraudulent. In the tax shelter area, this substantially reduces the ethical or legal uncertainty that otherwise presents an obstacle to the development of compliance norms in organizations. The paper identifies elements of this story that do not fit neatly under the classic economic analysis of tax avoidance or evasion, including the importance of enforcement outside the tax context and the particular power of clear government rules. The paper argues that this norm development story could provide a blueprint for regulatory attacks on deviant transactions but contends that it offers different lessons for regulatory challenges in greyer areas, pointing to a more cooperative approach. It also sketches the challenges of a cost-benefit analysis of such culturally sensitive regulatory strategies

The influence of power and actor relations on priority setting and resource allocation practices at the hospital level in Kenya: a case study

Abstract Background Priority setting and resource allocation in healthcare organizations often involves the balancing of competing interests and values in the context of hierarchical and politically complex settings with multiple interacting actor relationships. Despite this, few studies have examined the influence of actor and power dynamics on priority setting practices in healthcare organizations. This paper examines the influence of power relations among different actors on the implementation of priority setting and resource allocation processes in public hospitals in Kenya. Methods We used a qualitative case study approach to examine priority setting and resource allocation practices in two public hospitals in coastal Kenya. We collected data by a combination of in-depth interviews of national level policy makers, hospital managers, and frontline practitioners in the case study hospitals (n = 72), review of documents such as hospital plans and budgets, minutes of meetings and accounting records, and non-participant observations in case study hospitals over a period of 7 months. We applied a combination of two frameworks, Norman Long’s actor interface analysis and VeneKlasen and Miller’s expressions of power framework to examine and interpret our findings Results The interactions of actors in the case study hospitals resulted in socially constructed interfaces between: 1) senior managers and middle level managers 2) non-clinical managers and clinicians, and 3) hospital managers and the community. Power imbalances resulted in the exclusion of middle level managers (in one of the hospitals) and clinicians and the community (in both hospitals) from decision making processes. This resulted in, amongst others, perceptions of unfairness, and reduced motivation in hospital staff. It also puts to question the legitimacy of priority setting processes in these hospitals. Conclusions Designing hospital decision making structures to strengthen participation and inclusion of relevant stakeholders could improve priority setting practices. This should however, be accompanied by measures to empower stakeholders to contribute to decision making. Strengthening soft leadership skills of hospital managers could also contribute to managing the power dynamics among actors in hospital priority setting processes