Methods For Evaluation Of Evidence Research Articles

Values and evidence: how models make a difference

We call attention to an underappreciated way in which non-epistemic values influence evidence evaluation in science. Our argument draws upon some well-known features of scientific modeling. We show that, when scientific models stand in for background knowledge in Bayesian and other probabilistic methods for evidence evaluation, conclusions can be influenced by the non-epistemic values that shaped the setting of priorities in model development. Moreover, it is often infeasible to correct for this influence. We further suggest that, while this value influence is not particularly prone to the problem of wishful thinking, it could have problematic non-epistemic consequences in some cases.

Information‐Theoretical Assessment of the Performance of Likelihood Ratio Computation Methods

Performance of likelihood ratio (LR) methods for evidence evaluation has been represented in the past using, for example, Tippett plots. We propose empirical cross-entropy (ECE) plots as a metric of accuracy based on the statistical theory of proper scoring rules, interpretable as information given by the evidence according to information theory, which quantify calibration of LR values. We present results with a case example using a glass database from real casework, comparing performance with both Tippett and ECE plots. We conclude that ECE plots allow clearer comparisons of LR methods than previous metrics, allowing a theoretical criterion to determine whether a given method should be used for evidence evaluation or not, which is an improvement over Tippett plots. A set of recommendations for the use of the proposed methodology by practitioners is also given.

Guidelines for Chronic Obstructive Pulmonary Disease Treatment and Issues of Implementation

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. Treatment advances over the last decade, although limited, have precipitated the development of clinical practice guidelines, with the aim of improving the quality of care received by patients through fostering evidence-based decision making and accelerating the application of new advances to everyday practice. Of the COPD guidelines that have been developed, those developed through the Global Initiative for Chronic Obstructive Lung Disease (GOLD), initially a joint activity between the U.S. National Heart, Lung, and Blood Institute and the World Health Organization, and the National Institute of Clinical Excellence (NICE) in the United Kingdom have both published their methods for evaluation of evidence. These comprehensive guidelines cover all aspects of the disease, with the aim of providing the basis for local care pathways. The guideline development process includes evaluation of the evidence, development of the guideline, and dissemination of the findings. Efforts to enhance guideline effectiveness have focused on improving the methods and approaches to implementation, which requires an appreciation of the issues that stop translation of guideline definitions of best practice into improved patient care. A variety of questions remain unanswered in the clinical management of COPD, including the definition of outcome measures that move beyond lung function, the potential application of multidimensional grading systems that assess respiratory and systemic expressions of COPD and that could possibly better categorize and predict outcome in these patients, and the impact of new clinical trial findings. Large ongoing outcome studies may also have an effect on defining best practice within future guideline recommendations.