12 resultados para reference value

em Deakin Research Online - Australia


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Objective Transparent evidence-based decision making has been promoted worldwide to engender trust in science and policy making. Yet, little attention has been given to transparency implementation. The degree of transparency (focused on how uncertain evidence was handled) during the development of folate and vitamin D Dietary Reference Values was explored in three a priori defined areas: (i) value request; (ii) evidence evaluation; and (iii) final values. Design Qualitative case studies (semi-structured interviews and desk research). A common protocol was used for data collection, interview thematic analysis and reporting. Results were coordinated via cross-case synthesis. Setting Australia and New Zealand, Netherlands, Nordic countries, Poland, Spain and UK. Subjects Twenty-one interviews were conducted in six case studies. Results Transparency of process was not universally observed across countries or areas of the recommendation setting process. Transparency practices were most commonly seen surrounding the request to develop reference values (e.g. access to risk manager/assessor problem formulation discussions) and evidence evaluation (e.g. disclosure of risk assessor data sourcing/evaluation protocols). Fewer transparency practices were observed to assist with handling uncertainty in the evidence base during the development of quantitative reference values. Conclusions Implementation of transparency policies may be limited by a lack of dedicated resources and best practice procedures, particularly to assist with the latter stages of reference value development. Challenges remain regarding the best practice for transparently communicating the influence of uncertain evidence on the final reference values. Resolving this issue may assist the evolution of nutrition risk assessment and better inform the recommendation setting process.

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There is little strong evidence that currently recommended higher waist circumference cut-points for Europids compared with South Asians are associated with similar risk for type 2 diabetes. This study was designed to provide such evidence. Longitudinal studies over 5 years were conducted among 5,515 Europid and 2,214 ethnically South Asian participants. Age-standardized diabetes incidence at different levels of waist circumference and incidence difference relative to a reference value were calculated. The Youden Index was used to determine waist circumference cut-points. At currently recommended cut-points, estimated annual diabetes incidence for a 50-year-old Europid was <0.6% for both sexes, and for a 50-year-old South Asian, 5.8% for men and 2.1% for women. Annual diabetes incidence of 1% was observed for a 50 year old at a waist circumference 35–40 cm greater in Europid compared to South Asian men and women. Incidence difference between recommended cut-points and a reference value (80 cm in men, 70 cm in women) was 0.3 and 4.4% per year for Europid and South Asian men, and 0.2 and 0.8% per year for Europid and South Asian women, respectively. Waist circumference cut-points chosen using the Youden Index were shown to be dependent on obesity levels in the population. The much higher observed risk of diabetes in South Asians compared to Europids at the respective recommended waist circumference cut-points suggests that differences between them should be greater. Approaches that use the Youden Index to select waist circumference cut-points are inappropriate and should not be used for this purpose.

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This conceptual paper focuses on brand value for non-traditional products, and particularly, brand value in relation to Australian Football League Clubs, and its measurement. The concept of brand value has been addressed by a plethora of definitions and models in the literature, many of which focus on the measurement of brand value within traditional product industries. These models are often contingent on the intrinsic utility of the product itself, yet within non-traditional product areas, the product and the brand may be two distinct entities which should be differentiated in order to facilitate an accurate measurement of consumer-based brand value. To date, there has been limited research in this area and the general aim of this paper is to reveal the gaps in the current literature by providing an extension of traditional brand valuation theory to a non-traditional field. This paper illustrates its points with reference to a relevant model associated with “traditional” brand theories, and shows how it can be applied to the area of Australian Football League Clubs. This paper argues for the configuration of a more holistic model of brand value, including the antecedents and consequences of the value ascribed to brands by consumers, in order to encourage future research in brand equity based on the total utility derived from Australian Football League Clubs’ brands.

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Culture for Bordetella pertussis (B. pertussis) is the traditional gold standard for laboratory diagnosis of pertussis but is insensitive, especially later in the course of illness and in vaccinated persons. Interpretation of serology is limited by the lack of an appropriate reference standard. An outbreak of pertussis in a crowded boarding-school dormitory allowed evaluation of laboratory correlates of infection. Questionnaires, serum samples and throat swabs were collected from members of the exposed group. Serum samples from unexposed controls of a similar age group were used for comparison. B. pertussis PCR was performed on throat swabs, and sera were tested for IgA antibodies against whole-cell (WC) B. pertussis antigen and IgG antibodies to pertussis toxin (PT). The Centers for Disease Control and Prevention definition for pertussis was used to define clinical cases. We evaluated the use of a previously published cut-off for PT IgG of 125 EIA units (EU)/ml. Completed questionnaires were obtained from 115 students, of whom 85 (74%) reported coughing symptoms, including 32 (28%) who met the clinical case definition for pertussis. B. pertussis was detected by PCR in 17 (15%) and WC IgA in 22 (19%) students; neither correlated with symptoms, but dormitory of residence strongly predicted PCR status. The mean PT IgG geometric mean concentration, in this situation of high pertussis exposure, correlated with severity of symptoms and was significantly higher in both symptomatic and asymptomatic children exposed during the outbreak (P<0·001) than in control children. A cut-off for PT IgG of 125 EU/ml was too high in an outbreak situation to be sensitive enough to identify pertussis cases. A case of pertussis in a crowded boarding-school dormitory resulted rapidly in an outbreak. Serology and PCR were useful in identifying the outbreak and commencing disease control measures. The use of serology has mostly been evaluated in community serosurveys, where it is not possible to determine if immunity reflects vaccination, asymptomatic disease or symptomatic disease. This outbreak gave us the opportunity to evaluate the value of serology and PCR in the presence of confirmed exposure to pertussis.

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Ant-like agents forage between two points. These agents' probabilistic movements are based on the use of two pheromones; one marking trails towards the goal and another marking trails back to the starting point. Path selection decisions are influenced by the relative levels of attractive and repulsive pheromone in each agent's local environment. Our work in [5] evaluates three pheromone perception strategies, investigating path formation speed, quality, directionality, robustness and adaptability under different parameter settings(degree of randomness, pheromone evaporation rate and pheromone diffusion rate). We re-evaluate two of these strategies in terms of the amount of information they provide using Shannon's formulation [3, 4, 8, 9, 12, 14, 15, 16, 17]. We determine information as the difference between uncertainty before and after path selection decisions. Our focus in this paper is on investigating relationships between the emergence of the shortest path and the amount of stigmergic information that exists in the form of pheromone. Agents are deployed centrally and emergence measures are determined using the worst, reference and best cases observed in [5]. Additionally, the amount of local and global information that is available to agents in each movement step is evaluated. Furthermore, Pearson's correlation coefficients between measures of emergence and the amount of information are calculated. The significance of these correlation coefficients is tested using a 2 tailed test at 1% level of significance. Consequently the relationship between the amount of information and emergent behaviour is established. Significant relationships between information and the emergence of the shortest path exist when strong emergent behaviour is present.

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Fracture risk is determined by bone mineral density (BMD). The T-score, a measure of fracture risk, is the position of an individual's BMD in relation to a reference range. The aim of this study was to determine the magnitude of change in the T-score when different sampling techniques were used to produce the reference range. Reference ranges were derived from three samples, drawn from the same region: (1) an age-stratified population-based random sample, (2) unselected volunteers, and (3) a selected healthy subset of the population-based sample with no diseases or drugs known to affect bone. T-scores were calculated using the three reference ranges for a cohort of women who had sustained a fracture and as a group had a low mean BMD (ages 35-72 yr; n = 484). For most comparisons, the T-scores for the fracture cohort were more negative using the population reference range. The difference in T-scores reached 1.0 SD. The proportion of the fracture cohort classified as having osteoporosis at the spine was 26, 14, and 23% when the population, volunteer, and healthy reference ranges were applied, respectively. The use of inappropriate reference ranges results in substantial changes to T-scores and may lead to inappropriate management.

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The prevailing approach to the problem of the ontological status of mathematical entities such as numbers and sets is to ask in what sense it is legitimate to ascribe a reference to abstract singular terms; those expressions of our language which, taken at face value, denote abstract objects. On the basis of this approach, neo-Fregean Abstractionists such as Hale and Wright have argued that abstract singular terms may be taken to effect genuine reference towards objects, whereas nominalists such as Field have asserted that these apparent ontological commitments should not be taken at face value. In this article I argue for an intermediate position which upholds the legitimacy of ascribing a reference to abstract singular terms in an attenuated sense relative to the more robust ascription of reference applicable to names denoting concrete entities. In so doing I seek to clear up some confusions regarding the ramifications of such a thin notion of reference for ontological claims about mathematical objects.

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Frame analysis has been applied in Information Systems (IS) research to generate understanding of such issues as organisational change and IS implementation. Frames are the unconscious interpretive schemas that people, or groups of people, use to interpret their surroundings, determine what is important, and guide their actions. While framing has been used as a theoretical lens in IS research into organisations, there has been no analysis to date of how frames may play a role in the IS field itself. This paper argues that is relevant and insightful to examine the IS discourse from a framing perspective. In order to demonstrate the potential value of such an approach, a subset of a collection of articles from six journals in the senior scholars’ basket of journals was analysed in an exploratory attempt to locate the frames of reference that predominate in the IS discourse. Three levels of framing were identified and a provisional schema is proposed. We suggest that further investigation of the schema, the frames and their application will provide opportunity for critical reflection on the nature of Information Systems as an academic discipline. Such critical self-examination may even foster purposive frame breaking, in support of recent calls for transformation in the IS field.

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Reference features of a fatigue fracture surface are the reference texture and reference crack growth rate which are unambiguously mutually related. The reference texture is a subset of the image texture in SEM fractographs. It is expected to be common to all fractures caused by loadings in which significant events occur sufficiently regularly and frequently. The ratio of the reference and the conventional crack growth rate called reference factor is a characteristic of a particular loading. Its value may be related to the sequence of successive sizes of the cyclic plastic zone, while the mechanism of the effect of overloads follows the models of Wheeler and Willenborg. Application to a set of nine test specimens from aluminium alloy loaded by three different loading regimes is shown.

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Transparent evidence-based decision making has been promoted worldwide to engender trust in science and policy making. Yet, little attention has been given to transparency implementation. The degree of transparency (focused on how uncertain evidence was handled) during the development of folate and vitamin D Dietary Reference Values was explored in three a priori defined areas: (i) value request; (ii) evidence evaluation; and (iii) final values.