116 resultados para COMPETING-RISKS REGRESSION
em CentAUR: Central Archive University of Reading - UK
Resumo:
The differential transmission of alleles from parents to affected children indicates that the locus under investigation is either directly involved in the occurrence of the disease or that there are allelic associations with other loci that are directly involved. Conditional logistic regression applied to a diallelic locus leads to a test with two degrees of freedom. The power of a single degree of freedom test to detect non-multiplicative allelic effects is discussed here.
Resumo:
Travellers’ diarrhoea (TD) is the most common gastrointestinal illness to affect athletes competing abroad. Consequences of this debilitating condition include difficulties with training and/or participating in competitions which the athlete may have spent several years preparing for. Currently, there are no targeted strategies to reduce TD incidence in athletes. General methods used to reduce TD risk, such as avoidance of contaminated foods, chemoprophylactics and immunoprophylactics, have disadvantages. Since most causative agents of TD are microbial, strategies to minimise TD risks may be better focused on the gut microbiota. Prebiotics and probiotics can fortify the gut microbial balance, thus potentially aiding the fight against TD-associated microorganisms. Specific probiotics have shown promising actions against TD-associated microorganisms through antimicrobial activities. Use of prebiotics has led to an improved intestinal microbial balance which may be better equipped to combat TD-associated microorganisms. Both approaches have shown promising results in general travelling populations; therefore, a targeted approach for athletes has the potential to provide a competitive advantage.
Resumo:
What is the impact of the economy on cross national variation in far right-wing party support? This paper tests several hypotheses from existing literature on the results of the last three EP elections in all EU member states. We conceptualise the economy affects support because unemployment heightens the risks and costs that the population faces, but this is crucially mediated by labour market institutions. Findings from multiple regression analyses indicate that unemployment, real GDP growth, debt and deficits have no statistically significant effect on far right-wing party support at the national level. By contrast, labour markets influence costs and risks: where unemployment benefits and dismissal regulations are high, unemployment has no effect, but where either one of them is low, unemployment leads to higher far right-wing party support. This explains why unemployment has not led to far right-wing party support in some European countries that experienced the 2008 Eurozone crisis.
Resumo:
Incorporation of radioactive isotopes during the formation of barite mineral scale is a widespread phenomenon occurring within the oil, mining and process industries. In a series of experiments radioactive barite/celestite solid solutions (SSBarite-Celcstite) have been synthesized under controlled conditions by the counter diffusion of Ra-226, Ba2+, Sr24+ and SO42- ions through a porous medium (silica gel), to investigate inhibiting effects in Ra uptake associated with the introduction of a competing ion (Sr2+). From characterization studies, the particle size and the morphology of the crystals appear to be related to the initial [Sr]/[Ba] molar ratio of the starting solution. Typically, systems richer in Sr produce smaller sized crystals and clusters characterized by a lower degree of order. The activity introduced to the system is mainly incorporated in the crystals generated from the barite/celestite solid solution as suggested by the activity profiles of the hydrogel columns analysed by gamma-spectrometry. There is a relationship between the initial [Sr]/[Ba] molar ratio of the starting solution and the activity exhibited by the synthesized crystals. An effective inhibition of the Ra-226 uptake during formation of the crystals (SSBarite-Celestite) was obtained through the introduction of a competing ion (Sr2+): the higher the initial [Sr]/[Ba] molar ratio of the starting solution, the lower the intensity of the activity peak in the crystals. (C) 2003 Published by Elsevier Ltd.
Resumo:
Objectives - To assess the general public's interpretation of the verbal descriptors for side effect frequency recommended for use in medicine information leaflets by a European Union (EU) guideline, and to examine the extent to which differences in interpretation affect people's perception of risk and their judgments of intention to comply with the prescribed treatment. Method - Two studies used a controlled empirical methodology in which people were presented with a hypothetical, but realistic, scenario about visiting their general practitioner and being prescribed medication. They were given an explanation that focused on the side effects of the medicine, together with information about the probability of occurrence using either numerical percentages or the corresponding EU verbal descriptors. Interpretation of the descriptors was assessed. In study 2, participants were also required to make various judgments, including risk to health and intention to comply. Key findings - In both studies, use of the EU recommended descriptors led to significant overestimations of the likelihood of particular side effects occurring. Study 2 further showed that the "overestimation" resulted in significantly increased ratings of perceived severity of side effects and risk to health, as well as significantly reduced ratings of intention to comply, compared with those for people who received the probability information in numerical form. Conclusion - While it is recognised that the current findings require replication in a clinical setting, the European and national authorities should suspend the use of the EU recommended terms until further research is available to allow the use of an evidence-based approach.
Resumo:
A simple and practical technique for assessing the risks, that is, the potential for error, and consequent loss, in software system development, acquired during a requirements engineering phase is described. The technique uses a goal-based requirements analysis as a framework to identify and rate a set of key issues in order to arrive at estimates of the feasibility and adequacy of the requirements. The technique is illustrated and how it has been applied to a real systems development project is shown. How problems in this project could have been identified earlier is shown, thereby avoiding costly additional work and unhappy users.
Determinants of fruit and vegetable intake in England: a re-examination based on quantile regression
Resumo:
Objective To examine die sociodemographic determinants of fruit and vegetable (F&V) consumption in England and determine the differential effects of socioeconomic variables at various parts of the intake distribution, with a special focus on severely inadequate intakes Design Quantile regression, expressing F&V intake as a function of sociodemographic variables, is employed. Here, quantile regression flexibly allows variables such as ethnicity to exert effects on F&V intake that. vary depending oil existing levels of intake. Setting The 2003 Health survey of England. Subjects Data were from 11044 adult individuals. Results The influence of particular sociodemographic variables is found to vary significantly across the intake distribution We conclude that women consume more F&V than men, Asians and Hacks mole dian Whites, co-habiting individuals more than single-living ones Increased incomes and education also boost intake However, the key general finding of the present study is that the influence of most variables is relatively weak in the area of greatest concern, i e among those with the most inadequate intakes in any reference group. Conclusions. Our findings emphasise the importance of allowing the effects of socio-economic drivers to vary across the intake distribution The main finding, that variables which exert significant influence on F&V Intake at other parts Of the conditional distribution have a relatively weak influence at the lower tail, is cause for concern. It implies that in any defined group, those consuming the lease F&V are hard to influence using compaigns or policy levers.