286 research outputs found

    The Grammar of the Reporting of Qualitative Research

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    The utility of research has been discussed in many arenas and for many reasons over the past few years. Given that most research is disseminated via reports and papers, the medium through which research is used has also been under scrutiny. Often, the quality of reporting has been criticised. This is particularly evident in health-related areas where many reporting guidelines have been developed. While some of this debate has surfaced in social science disciplines, there has not been the same level of activity in developing guidelines. One exception is REPOSE - developed for use in educational research. The authors of these guidelines found that some aspects of research were inadequately reported and that authors’ guidance given by journals does not, in the main, specify how the research itself should be reported

    Using framework-based synthesis for conducting reviews of qualitative studies

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    Framework analysis is a technique used for data analysis in primary qualitative research. Recent years have seen its being adapted to conduct syntheses of qualitative studies. Framework-based synthesis shows considerable promise in addressing applied policy questions. An innovation in the approach, known as 'best fit' framework synthesis, has been published in BMC Medical Research Methodology this month. It involves reviewers in choosing a conceptual model likely to be suitable for the question of the review, and using it as the basis of their initial coding framework. This framework is then modified in response to the evidence reported in the studies in the reviews, so that the final product is a revised framework that may include both modified factors and new factors that were not anticipated in the original model. 'Best fit' framework-based synthesis may be especially suitable in addressing urgent policy questions where the need for a more fully developed synthesis is balanced by the need for a quick answer

    Cost-Effectiveness of a national initiative to improve hand hygiene compliance using the outcome of healthcare associated staphylococcus aureus bacteraemia

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    © 2016 Graves et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background The objective is to estimate the incremental cost-effectiveness of the Australian National Hand Hygiene Inititiave implemented between 2009 and 2012 using healthcare associated Staphylococcus aureus bacteraemia as the outcome. Baseline comparators are the eight existing state and territory hand hygiene programmes. The setting is the Australian public healthcare system and 1,294,656 admissions from the 50 largest Australian hospitals are included. Methods The design is a cost-effectiveness modelling study using a before and after quasi-experimental design. The primary outcome is cost per life year saved from reduced cases of healthcare associated Staphylococcus aureus bacteraemia, with cost estimated by the annual on-going maintenance costs less the costs saved from fewer infections. Data were harvested from existing sources or were collected prospectively and the time horizon for the model was 12 months, 2011-2012. Findings No useable pre-implementation Staphylococcus aureus bacteraemia data were made available from the 11 study hospitals in Victoria or the single hospital in Northern Territory leaving 38 hospitals among six states and territories available for cost-effectiveness analyses. Total annual costs increased by 2,851,475forareturnof96yearsoflifegivinganincrementalcosteffectivenessratio(ICER)of2,851,475 for a return of 96 years of life giving an incremental cost-effectiveness ratio (ICER) of 29,700 per life year gained. Probabilistic sensitivity analysis revealed a 100% chance the initiative was cost effective in the AustralianCapital Territory and Queensland, with ICERs of 1,030and1,030 and 8,988 respectively. There was an 81% chance it was cost effective in New South Wales with an ICER of 33,353,a2633,353, a 26% chance for South Australia with an ICER of 64,729 and a 1% chance for Tasmania and Western Australia. The 12 hospitals in Victoria and the Northern Territory incur annual on-going maintenance costs of 1.51M;noinformationwasavailabletodescribecostsavingsorhealthbenefits.ConclusionsTheAustralianNationalHandHygieneInitiativewascosteffectiveagainstanAustralianthresholdof1.51M; no information was available to describe cost savings or health benefits. Conclusions The Australian National Hand Hygiene Initiative was cost-effective against an Australian threshold of 42,000 per life year gained. The return on investment varied among the states and territories of Australia

    Improved algebraic cryptanalysis of QUAD, Bivium and Trivium via graph partitioning on equation systems

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    We present a novel approach for preprocessing systems of polynomial equations via graph partitioning. The variable-sharing graph of a system of polynomial equations is defined. If such graph is disconnected, then the corresponding system of equations can be split into smaller ones that can be solved individually. This can provide a tremendous speed-up in computing the solution to the system, but is unlikely to occur either randomly or in applications. However, by deleting certain vertices on the graph, the variable-sharing graph could be disconnected in a balanced fashion, and in turn the system of polynomial equations would be separated into smaller systems of near-equal sizes. In graph theory terms, this process is equivalent to finding balanced vertex partitions with minimum-weight vertex separators. The techniques of finding these vertex partitions are discussed, and experiments are performed to evaluate its practicality for general graphs and systems of polynomial equations. Applications of this approach in algebraic cryptanalysis on symmetric ciphers are presented: For the QUAD family of stream ciphers, we show how a malicious party can manufacture conforming systems that can be easily broken. For the stream ciphers Bivium and Trivium, we nachieve significant speedups in algebraic attacks against them, mainly in a partial key guess scenario. In each of these cases, the systems of polynomial equations involved are well-suited to our graph partitioning method. These results may open a new avenue for evaluating the security of symmetric ciphers against algebraic attacks

    RAMESES publication standards: realist syntheses

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    PMCID: PMC3558331This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

    Baryogenesis from Primordial Blackholes after Electroweak Phase Transition

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    Incorporating a realistic model for accretion of ultra-relativistic particles by primordial blackholes (PBHs), we study the evolution of an Einstein-de Sitter universe consisting of PBHs embedded in a thermal bath from the epoch 1033\sim 10^{-33} sec to 5×109\sim 5\times 10^{-9} sec. In this paper we use Barrow et al's ansatz to model blackhole evaporation in which the modified Hawking temperature goes to zero in the limit of the blackhole attaining a relic state with mass mpl\sim m_{pl}. Both single mass PBH case as well as the case in which blackhole masses are distributed in the range 8×1023×1058\times 10^2 - 3\times 10^5 gm have been considered in our analysis. Blackholes with mass larger than 105\sim 10^5 gm appear to survive beyond the electroweak phase transition and, therefore, successfully manage to create baryon excess via XXˉX-\bar X emissions, averting the baryon number wash-out due to sphalerons. In this scenario, we find that the contribution to the baryon-to-entropy ratio by PBHs of initial mass mm is given by ϵζ(m/1gm)1\sim \epsilon \zeta (m/1 {gm})^{-1}, where ϵ\epsilon and ζ\zeta are the CP-violating parameter and the initial mass fraction of the PBHs, respectively. For ϵ\epsilon larger than 104\sim 10^{-4}, the observed matter-antimatter asymmetry in the universe can be attributed to the evaporation of PBHs.Comment: Latex2e file with seven figures included as postscript file

    A worked example of "best fit" framework synthesis: A systematic review of views concerning the taking of some potential chemopreventive agents

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    <p>Abstract</p> <p>Background</p> <p>A variety of different approaches to the synthesis of qualitative data are advocated in the literature. The aim of this paper is to describe the application of a pragmatic method of qualitative evidence synthesis and the lessons learned from adopting this "best fit" framework synthesis approach.</p> <p>Methods</p> <p>An evaluation of framework synthesis as an approach to the qualitative systematic review of evidence exploring the views of adults to the taking of potential agents within the context of the primary prevention of colorectal cancer.</p> <p>Results</p> <p>Twenty papers from North America, Australia, the UK and Europe met the criteria for inclusion. Fourteen themes were identified <it>a priori </it>from a related, existing conceptual model identified in the literature, which were then used to code the extracted data. Further analysis resulted in the generation of a more sophisticated model with additional themes. The synthesis required a combination of secondary framework and thematic analysis approaches and was conducted within a health technology assessment timeframe.</p> <p>Conclusion</p> <p>The novel and pragmatic "best fit" approach to framework synthesis developed and described here was found to be fit for purpose. Future research should seek to test further this approach to qualitative data synthesis.</p

    Experiences of Self-Management Support Following a Stroke: A Meta-Review of Qualitative Systematic Reviews

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    Supporting self-management in stroke patients improves psychological and functional outcomes but evidence on how to achieve this is sparse. We aimed to synthesise evidence from systematic reviews of qualitative studies in an overarching meta-review to inform the delivery and development of self-management support interventions.We systematically searched eight electronic databases including MEDLINE, EMBASE and CINAHL for qualitative systematic reviews (published January 1993 to June 2012). We included studies exploring patients', carers' or health care professionals' experiences relevant to self-management support following a stroke, including studies describing the lived experience of surviving a stroke. We meta-synthesised the included review findings using a meta-ethnographic framework.Seven reviews, reporting 130 unique studies, were included. Themes emerging from the reviews were pertinent, consistent and showed data saturation; though explicit mention of self-management support was rare. Our meta-review highlighted the devastating impact of stroke on patients' self-image; the varying needs for self-management support across the trajectory of recovery; the need for psychological and emotional support throughout recovery particularly when physical recovery plateaus; the considerable information needs of patients and carers which also vary across the trajectory of recovery; the importance of good patient-professional communication; the potential benefits of goal-setting and action-planning; and the need for social support which might be met by groups for stroke survivors.The observed data saturation suggests that, currently, no further qualitative research simply describing the lived experience of stroke is needed; we propose that it would be more useful to focus on qualitative research informing self-management support interventions and their implementation. Our findings demonstrate both the on-going importance of self-management support and the evolving priorities throughout the stages of recovery following a stroke. The challenge now is to ensure these findings inform routine practice and the development of interventions to support self-management amongst stroke survivors

    Realist synthesis : illustrating the method for implementation research

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    BackgroundRealist synthesis is an increasingly popular approach to the review and synthesis of evidence, which focuses on understanding the mechanisms by which an intervention works (or not). There are few published examples of realist synthesis. This paper therefore fills a gap by describing, in detail, the process used for a realist review and synthesis to answer the question \u27what interventions and strategies are effective in enabling evidence-informed healthcare?\u27 The strengths and challenges of conducting realist review are also considered. MethodsThe realist approach involves identifying underlying causal mechanisms and exploring how they work under what conditions. The stages of this review included: defining the scope of the review (concept mining and framework formulation); searching for and scrutinising the evidence; extracting and synthesising the evidence; and developing the narrative, including hypotheses. ResultsBased on key terms and concepts related to various interventions to promote evidenceinformed healthcare, we developed an outcome-focused theoretical framework. Questions were tailored for each of four theory/intervention areas within the theoretical framework and were used to guide development of a review and data extraction process. The search for literature within our first theory area, change agency, was executed and the screening procedure resulted in inclusion of 52 papers. Using the questions relevant to this theory area, data were extracted by one reviewer and validated by a second reviewer. Synthesis involved organisation of extracted data into evidence tables, theming and formulation of chains of inference, linking between the chains of inference, and hypothesis formulation. The narrative was developed around the hypotheses generated within the change agency theory area. ConclusionsRealist synthesis lends itself to the review of complex interventions because it accounts for context as well as outcomes in the process of systematically and transparently synthesising relevant literature. While realist synthesis demands flexible thinking and the ability to deal with complexity, the rewards include the potential for more pragmatic conclusions than alternative approaches to systematic reviewing. A separate publication will report the findings of the review. <br /
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