318 research outputs found
Competition between exchanges : Euronext versus Xetra
Exchanges in Europe are in a process of consolidation. After the failure of the proposed merger between Deutsche Börse and Euronext, these two groups are likely to become the nuclei for further mergers and co-operation with currently independent exchanges. A decision for one of the groups entails a decision for the respective trading platform. Against that background we evaluate the attractiveness of the two dominant continental European trading systems. Though both are anonymous electronic limit order books, there are important differences in the trading protocols. We use a matched-sample approach to compare execution costs in Euronext Paris and Xetra. We find that both quoted and effective spreads are lower in Xetra. When decomposing the spread we find no systematic differences in the adverse selection component. Realized spreads, on the other hand, are significantly higher in Euronext. Neither differences in the number of liquidity provision agreements nor differences in the minimum tick size or in the degree of domestic competition for order flow explain the different spread levels. We thus conclude that Xetra is the more efficient trading system. JEL Classification: G10, G1
Essential Oils of Umbelliferae (Apiaceae) Family Taxa as Emerging Potent Agents for Mosquito Control
Patient engagement in designing, conducting, and disseminating clinical pain research: IMMPACT recommended considerations
In the traditional clinical research model, patients are typically involved only as participants. However, there has been a shift in recent years highlighting the value and contributions that patients bring as members of the research team, across the clinical research lifecycle. It is becoming increasingly evident that to develop research that is both meaningful to people who have the targeted condition and is feasible, there are important benefits of involving patients in the planning, conduct, and dissemination of research from its earliest stages. In fact, research funders and regulatory agencies are now explicitly encouraging, and sometimes requiring, that patients are engaged as partners in research. Although this approach has become commonplace in some fields of clinical research, it remains the exception in clinical pain research. As such, the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials convened a meeting with patient partners and international representatives from academia, patient advocacy groups, government regulatory agencies, research funding organizations, academic journals, and the biopharmaceutical industry to develop consensus recommendations for advancing patient engagement in all stages of clinical pain research in an effective and purposeful manner. This article summarizes the results of this meeting and offers considerations for meaningful and authentic engagement of patient partners in clinical pain research, including recommendations for representation, timing, continuous engagement, measurement, reporting, and research dissemination
Obstructive sleep apnea as an independent predictor of postoperative delirium and pain: Protocol for an observational study of a surgical cohort [version 2; referees: 2 approved]
Introduction: Postoperative delirium and pain are common complications in adults, and are difficult both to prevent and treat. Obstructive sleep apnea (OSA) is prevalent in surgical patients, and has been suggested to be a risk factor for postoperative delirium and pain. OSA also might impact pain perception, and alter pain medication requirements. This protocol describes an observational study, with the primary aim of testing whether OSA is an independent predictor of postoperative complications, focusing on (i) postoperative incident delirium and (ii) acute postoperative pain severity. We secondarily hypothesize that compliance with prescribed treatment for OSA (typically continuous positive airway pressure or CPAP) might decrease the risk of delirium and the severity of pain. Methods and analysis: We will include data from patients who have been enrolled into three prospective studies: ENGAGES, PODCAST, and SATISFY-SOS. All participants underwent general anesthesia for a non-neurosurgical inpatient operation, and had a postoperative hospital stay of at least one day at Barnes Jewish Hospital in St. Louis, Missouri, from February 2013 to May 2018. Â Patients included in this study have been assessed for postoperative delirium and pain severity as part of the parent studies. In the current study, determination of delirium diagnosis will be based on the Confusion Assessment Method, and the Visual Analogue Pain Scale will be used for pain severity. Data on OSA diagnosis, OSA risk and compliance with treatment will be obtained from the preoperative assessment record. Other variables that are candidate risk factors for delirium and pain will also be extracted from this record. We will use logistic regression to test whether OSA independently predicts postoperative delirium and linear regression to assess OSAs relationship to acute pain severity. We will conduct secondary analyses with subgroups to explore whether these relationships are modified by compliance with OSA treatment.</ns4:p
Prediction of chronic postsurgical pain in adults: A protocol for multivariable prediciton model development
INTRODUCTION: Chronic postsurgical pain (CPSP) is a condition that affects an estimated 10%–50% of adults, depending on the surgical procedure. CPSP often interferes with activities of daily living and may have a negative impact on quality of life, emotional and physical well-being. Clinical prediction models can help clinicians target preventive strategies towards patients at high-risk of CPSP. Therefore, the objective of this study is to develop a clinically applicable and generalisable prediction model for CPSP in adults. METHODS AND ANALYSIS: This research will be a prospective single-centre observational cohort study in Denmark spanning approximately 1 year or until a predefined number of patients are recruited (n=1526). Adult patients aged 18 years and older scheduled to undergo surgery will be recruited at Aarhus University Hospital. The primary outcome is CPSP 3 months after surgery defined as average pain intensity at rest or on movement ≥3 on numerical rating scale (NRS) within the past week, and/or average pain interference ≥3 on NRS among any of seven short-form Brief Pain Inventory items in the past week (general activity, mood, walking ability, normal work (including housework), relations with other people, sleep and enjoyment of life). Logistic regression will be used to conduct multivariate analysis. Predictive model performance will be evaluated by discrimination, calibration and model classification. ETHICS AND DISSEMINATION: This research has been approved by Central Region Denmark and will be conducted in accordance with the Danish Data Protection Act and Declaration of Helsinki. Study findings will be disseminated through conference presentations and peer-reviewed publication. A CPSP risk calculator (CPSP-RC) will be developed based on predictors retained in the final models. The CPSP-RC will be made available online and as a mobile application to be easily accessible for clinical use and future research including validation and clinical impact assessments. TRIAL REGISTRATION NUMBER: NCT04866147
Factors associated with persistent postsurgical pain after total knee or hip joint replacement: A systematic review and meta-analysis
Studies have identified demographic, clinical, psychosocial, and perioperative variables associated with persistent pain after a variety of surgeries. This study aimed to perform a systematic review and meta-analysis of factors associated with persistent pain after total knee replacement (TKR) and total hip replacement (THR) surgeries. To meet the inclusion criteria, studies were required to assess variables before or at the time of surgery, include a persistent postsurgical pain (PPSP) outcome measure at least 2 months after a TKR or THR surgery, and include a statistical analysis of the effect of the risk factor(s) on the outcome measure. Outcomes from studies implementing univariate and multivariable statistical models were analyzed separately. Where possible, data from univariate analyses on the same factors were combined in a meta-analysis. Eighty-one studies involving 171,354 patients were included in the review. Because of the heterogeneity of assessment methods, only 44% of the studies allowed meaningful meta-analysis. In meta-analyses, state anxiety (but not trait anxiety) scores and higher depression scores on the Beck Depression Inventory were associated with an increased risk of PPSP after TKR. In the qualitative summary of multivariable analyses, higher preoperative pain scores were associated with PPSP after TKR or THR. This review systematically assessed factors associated with an increased risk of PPSP after TKR and THR and highlights current knowledge gaps that can be addressed by future research
Epidurals in Pancreatic Resection Outcomes (E-PRO) study: Protocol for a randomised controlled trial
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Transition equity markets of Central Europe: volatility, predictability, integration
The objective of this thesis is to add evidence from the transition equity markets of Central Europe to the econometric modelling of financial time series by addressing the issues of volatility, predictability and international asset pricing in these markets. In Chapter Two we start from an overview of the transition stock markets by presenting their historical background, basic regulations, statistics, and stock market indices. Chapter Three focuses on the modelling of univariate and multivariate volatility in transition equity markets. Our sample has all the previously documented characteristics of the unconditional distribution of stock returns normally used to justify the use of the GARCH class of the models of conditional volatility. Strong GARCH effects are apparent in all series examined. The estimates of asymmetric models of conditional volatility show rather weak evidence of asymmetries in the markets. The results of the multivariate specifications of volatility have implication for understanding the pattern of information flow between the markets. The constant correlation specification indicates significant conditional correlation between three pairs of countries: Hungary and Poland, Hungary and Czech Republic, and Poland and Czech Republic. The BEKK model of multivariate volatility shows evidence of return volatility spillovers from Hungary to Poland, but no volatility spillover effects are found in the opposite direction. Chapter Four examines the linear and nonlinear predictability of transition equity returns with simple technical trading rules. The application of the moving average trading rules to the data reveals that technical analysis helps to predict stock price changes. Firstly buy signals consistently generate higher returns than sell signals; secondly the returns following buy signals are less volatile than returns following sell signals. The application of the bootstrap methodology to check whether three popular null models of stock returns with linear conditional mean specification replicate the trading rule profits indicates that returns obtained from trading rules signals are not likely to be generated by these models. Comparison of the out-of-sample forecast performance of linear and nonlinear (feedforward networks) conditional mean estimators with past trading signals in the conditional mean equation indicates substantial forecast improvements of the feedforward network regression. Chapter Five addresses the issue of integration of the transition equity markets into the global capital market by testing pricing restrictions of the international CAPM simultaneously for four national equity markets: two developed markets (U.S. and Germany) and two new transition markets (Hungary and Poland). Methodologically, we extend the BEKK multivariate GARCH specification to accommodate GARCH-M effects, and propose an alternative specification of the conditional CAPM, which allows return volatility transmissions between the markets in the system. The results reveal that the world price of covariance risk is positive and equal across the markets. This is consistent with the international CAPM and supports the hypothesis of integration of the transition markets into the global market. However, our further results indicate individual significance of the Hungarian idiosyncratic risk, pointing to some level of segmentation of the Hungarian market. Moreover, the introduction of world-wide information variables into the system reveals that some variation in the excess national returns is still predictable after accounting for the measure of market-wide risk
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