Cost-effectiveness acceptability curves - facts, fallacies and frequently asked questions

Cost-effectiveness acceptability curves (CEACs) have been widely adopted as a method to quantify and graphically represent uncertainty in economic evaluation studies of health-care technologies. However, there remain some common fallacies regarding the nature and shape of CEACs that largely result from the textbook illustration of the CEAC. This textbook CEAC shows a smooth curve starting at probability 0, with an asymptote to 1 for higher money values of the health outcome (). But this familiar ogive shape which makes the textbook CEAC look like a cumulative distribution function is just one special case of the CEAC. The reality is that the CEAC can take many shapes and turns because it is a graphic transformation from the cost-effectiveness plane, where the joint density of incremental costs and effects may straddle quadrants with attendant discontinuities and asymptotes. In fact CEACs: (i) do not have to cut the y-axis at 0; (ii) do not have to asymptote to 1; (iii) are not always monotonically increasing in ; and (iv) do not represent cumulative distribution functions (cdfs). Within this paper we present a gallery of CEACs in order to identify the fallacies and illustrate the facts surrounding the CEAC. The aim of the paper is to serve as a reference tool to accompany the increased use of CEACs within major medical journals

Bayesian spatial analysis of a national urinary schistosomiasis questionnaire to assist geographic targeting of schistosomiasis control in Tanzania, East Africa.

Spatial modelling was applied to self-reported schistosomiasis data from over 2.5 million school students from 12,399 schools in all regions of mainland Tanzania. The aims were to derive statistically robust prevalence estimates in small geographical units (wards), to identify spatial clusters of high and low prevalence and to quantify uncertainty surrounding prevalence estimates. The objective was to permit informed decision-making for targeting of resources by the Tanzanian national schistosomiasis control programme. Bayesian logistic regression models were constructed to investigate the risk of schistosomiasis in each ward, based on the prevalence of self-reported schistosomiasis and blood in urine. Models contained covariates representing climatic and demographic effects and random effects for spatial clustering. Degree of urbanisation, median elevation of the ward and median normalised difference vegetation index (NDVI) were significantly and negatively associated with schistosomiasis prevalence. Most regions contained wards that had >95% certainty of schistosomiasis prevalence being >10%, the selected threshold for bi-annual mass chemotherapy of school-age children. Wards with >95% certainty of schistosomiasis prevalence being >30%, the selected threshold for annual mass chemotherapy of school-age children, were clustered in north-western, south-western and south-eastern regions. Large sample sizes in most wards meant raw prevalence estimates were robust. However, when uncertainties were investigated, intervention status was equivocal in 6.7-13.0% of wards depending on the criterion used. The resulting maps are being used to plan the distribution of praziquantel to participating districts; they will be applied to prioritising control in those wards where prevalence was unequivocally above thresholds for intervention and might direct decision-makers to obtain more information in wards where intervention status was uncertain

Origin and surface form of the Tsondab Sandstone Formation, central Namib desert

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. October 1990Problems arising from a disparity in viewpoints regarding the surface form of the Tsondab Sandstone Formation, central Namib desert, Namibia, are examined through literature review and field investigation. It is shown that large distal low-angle fans, proposed in what has been termed the Low-Angle Fan model, are absent or limited to proximal reaches of the study area. The depositional sequence identified in what has been termed the Axial Deposition Model along the Kuiseb River in the northern part of the study area is safely applicable to the rest of the study area. Further, new deposits of the Tsondab Sandstone Formation are identified. The problem of the age of the Namib desert in its fossil and active forms is discussed. The processing of satellite images is used and is shown not to be a viable technique for the identification of sedimentary bodies which are partly mantled by deposits of sediments of a similar nature.MT201

Rejecting Asymmetry of Access to Formal Relationship Statuses for Same and Different-Sex Couples at Strasbourg and Domestically

This article interrogates the extent to which the formal recognition and protection of same and different-sex relationships at Strasbourg and in domestic courts has been accepted as attracting human rights protection. In order to do so it considers how far equality of access to formalised relationship statuses as between same and different-sex couples has arisen in the ECHR contracting states. Inequality of access—asymmetry of access—arises, it will be argued, in its most obvious and pernicious form in those Eastern contracting states in which different-sex couples who wish to live together can access one of two options: cohabitation or marriage, while same-sex couples are confined to cohabitation only. But a form of asymmetry also arises in states which have introduced registered partnerships for same-sex couples, leaving availability of marriage only to different-sex ones. Other forms of asymmetry of access are also explored. This article argues for taking further steps towards creation of symmetry of access to formal relationship statuses in Member States on human rights grounds, but also pragmatically, in order to strengthen the consensus in the contracting states on this matter, and therefore place the Strasbourg Court more clearly at the forefront of addressing the inequalities thereby arising, where Member States have so far failed to do so

From same-sex marriage to equal civil partnerships: on a path towards ‘perfecting’ equality?

This article will consider the progress made towards achieving equality between same- and different-sex couples seeking formalisation of their relationships. It will do so by examining the extent to which the introduction of civil partnerships and same-sex marriage in England and Wales created equality of access to formal relationship statuses, and the benefits thereby accruing. Elimination of discrimination between same- and different-sex couples in this context was not achieved, as accepted by the Court of Appeal in Steinfeld and Keidan, which concerned a claim for a civil partnership under Articles 8 and 14 of the European Convention for the Protection of Human Rights and Fundamental Freedoms 1950 by a different-sex couple. The article will argue that nevertheless furtherance of equality, rather than dignity-based arguments, provided the driving force for change and that the next step taken towards equality requires the creation of symmetry of access to formalisation of relationships as between same- and different-sex couples. The Supreme Court in Steinfeld now has the opportunity of prompting the taking of that step, but this article further argues that recognition of the value of dignity in this context as linked to non-discrimination should shape the response of the government, either to that decision, or to its own ongoing review of the future of civil partnerships

National counter-terrorism (C-T) policies and challenges to human rights and civil liberties: Case study of United Kingdom

In the UK the rise post-2005 in “home-grown” terrorism, relying to a significant extent on strikes on soft targets by “self-starters,” means that the search for effective preventive measures remains a continuing concern. Below a number of the preventive counter-terror measures adopted post-9/11, and incrementally strengthened in response to the current threat, are found to fall into three categories and represent interventions at the stages in the path toward attacks. This chapter focuses on selected examples of these preventive measures. In terms of three key stages, firstly, there is the attempt to prevent radicalization, under the “Prevent” strategy. A second strategy relies on taking certain measures to control the activities of those considered likely – on the balance of probabilities – to engage in terrorist-related activity. A third preventive strategy relies on the special terrorism offences under the Terrorism Acts 2000 and 2006, as amended, intended to allow for intervention at a very early stage in terrorist plots and in preparing or instigating terrorist acts (“precursor” offences)

Catching up with the Present: A Proposal for Document Delivery in the Legal Profession

The high technology law practice. tracks the incredible pace of development in the computer industry. High tech practitioners are often instrumental in bringing new technologies to market, ensuring their protection from infringement, and structuring the relations and obligations that bring new products to the consumer. As advocates, they push for greater protection of emergent fields, either through new legislation or clearer definitions of existing law. And for all that computer law practitioners depend on technology for the lifeblood of their practice, there are numerous possibilities for increased efficiency based on this technology that are overlooked. In this article we propose a new protocol for exchanging information between law firms, one that will improve the practice of law as a whole by reducing the barriers to accessing information, increasing the efficiency of manipulating information, and ultimately, reducing the excessive costs faced by clients

Catching up with the Present: A Proposal for Document Delivery in the Legal Profession

The high technology law practice. tracks the incredible pace of development in the computer industry. High tech practitioners are often instrumental in bringing new technologies to market, ensuring their protection from infringement, and structuring the relations and obligations that bring new products to the consumer. As advocates, they push for greater protection of emergent fields, either through new legislation or clearer definitions of existing law. And for all that computer law practitioners depend on technology for the lifeblood of their practice, there are numerous possibilities for increased efficiency based on this technology that are overlooked. In this article we propose a new protocol for exchanging information between law firms, one that will improve the practice of law as a whole by reducing the barriers to accessing information, increasing the efficiency of manipulating information, and ultimately, reducing the excessive costs faced by clients