22 research outputs found

    Simplifying Embedded System Development Through Whole-Program Compilers

    Get PDF
    As embedded systems embrace ever more complicated microcontrollers, they present both new capability and new complexity. To simplify their development, some lessons of computer application development will translate with additional work. This thesis offers one such translation. It shows how whole-program compilers - those that broadly analyze a program\u27s entire source code - can achieve performance gains and remove faults in embedded system applications. In so doing, this yields a novel stackless threading system named UnStacked C. UnStacked C enables cooperative multithreading without the risk of stack overflows in embedded system applications. We also propose a novel preemption system called Lazy Preemption. Unstacked C with Lazy Preemption enables stackless preemptive multithreading in embedded systems. These remove the possibility of thread stack overflows, but also significantly reduces the memory required for multithreading in embedded system

    Erratum to: Methods for evaluating medical tests and biomarkers

    Get PDF
    [This corrects the article DOI: 10.1186/s41512-016-0001-y.]

    Evidence synthesis to inform model-based cost-effectiveness evaluations of diagnostic tests: a methodological systematic review of health technology assessments

    Get PDF
    Background: Evaluations of diagnostic tests are challenging because of the indirect nature of their impact on patient outcomes. Model-based health economic evaluations of tests allow different types of evidence from various sources to be incorporated and enable cost-effectiveness estimates to be made beyond the duration of available study data. To parameterize a health-economic model fully, all the ways a test impacts on patient health must be quantified, including but not limited to diagnostic test accuracy. Methods: We assessed all UK NIHR HTA reports published May 2009-July 2015. Reports were included if they evaluated a diagnostic test, included a model-based health economic evaluation and included a systematic review and meta-analysis of test accuracy. From each eligible report we extracted information on the following topics: 1) what evidence aside from test accuracy was searched for and synthesised, 2) which methods were used to synthesise test accuracy evidence and how did the results inform the economic model, 3) how/whether threshold effects were explored, 4) how the potential dependency between multiple tests in a pathway was accounted for, and 5) for evaluations of tests targeted at the primary care setting, how evidence from differing healthcare settings was incorporated. Results: The bivariate or HSROC model was implemented in 20/22 reports that met all inclusion criteria. Test accuracy data for health economic modelling was obtained from meta-analyses completely in four reports, partially in fourteen reports and not at all in four reports. Only 2/7 reports that used a quantitative test gave clear threshold recommendations. All 22 reports explored the effect of uncertainty in accuracy parameters but most of those that used multiple tests did not allow for dependence between test results. 7/22 tests were potentially suitable for primary care but the majority found limited evidence on test accuracy in primary care settings. Conclusions: The uptake of appropriate meta-analysis methods for synthesising evidence on diagnostic test accuracy in UK NIHR HTAs has improved in recent years. Future research should focus on other evidence requirements for cost-effectiveness assessment, threshold effects for quantitative tests and the impact of multiple diagnostic tests

    Erratum to: Methods for evaluating medical tests and biomarkers

    Get PDF
    [This corrects the article DOI: 10.1186/s41512-016-0001-y.]

    Falling down the rabbit hole? Methodological, conceptual and policy issues in current health inequalities research

    Get PDF
    Persistent health inequalities pose a challenge to researchers and policymakers. Decades of research have illuminated mechanisms that underlie health inequalities, now we must move beyond these observations to enable policies that can reduce them. In this paper, we highlight tensions in the field of health inequalities research regarding the relationship between social determinants and health outcomes, and the effectiveness of welfare policies. We draw on recent evidence to analyse and discuss these areas of debate and provide insight into the evidence on causality, welfare systems and policies aiming to address the social determinants of health inequalities. First, we examine the evidence that inequalities in the social determinants of health are causally related to health inequalities. Second, we discuss whether more egalitarian social policies provide a solution to redressing health inequalities. In conclusion, we suggest that current debates around causal understandings risk sending the field down ‘rabbit holes’ that distract from solution. We argue that, if we combine epidemiological evidence with the broader canon of social science evidence, the case for causal inference is sufficiently strong to suggest we now need to focus on effectively supporting and promoting research-informed policy responses to health inequalities

    References

    No full text
    corecore