非ST段抬高急性心肌梗死的心电图分析

目的探讨非典型心肌梗死在心电图中的表现及临床意义。方法随机抽取我院2006年1月至2008年1月门诊确诊的急性心肌梗死患者57例,对其临床资料及心电图表现进行探讨。结果 57例急性心肌梗死患者,出现非典型心电图形态20例,占35.08%。结论熟悉并掌握非典型心肌梗死的心电图形态改变对急性心肌梗死的诊断治疗及预后至关重要,防止出现误诊、漏诊现象,为临床提供准确的诊疗依据。     

临床路径在计划性剖宫产中的应用分析

目的:探讨临床路径在剖宫产这一单病种中的应用效果.方法:将2010年1～12月符合剖宫产临床路径实施条件的剖宫产术者作为研究对象,分析临床路径组与对照组的术前住院天数、平均住院日、住院费用、并发症、纠纷发生数及患者满意度等.结果:临床路径组术前住院天数、住院总天数减少;住院总费用略有降低,患者满意度上升.结论:临床路径的实施对保证医疗质量、控制医疗费用有一定的促进作用,是切实有效、可行的一种诊疗方式.     

论生物-心理-社会医学模式的临床应用

当前,国内医院生物-心理-社会医学模式推行缓慢,其主要原因是缺乏对这一模式科学内涵的全面理解,"以病人为中心"的医疗服务模式体现了生物-心理-社会医学模式的科学内涵,务必大力弘扬,以推进医学模式转变.     

Two-stage k-sample designs for the ordered alternative problem

In preclinical studies and clinical dose-ranging trials, the Jonckheere-Terpstra test is widely used in the assessment of dose-response relationships. Hewett and Spurrier (1979) presented a two-stage analog of the test in the context of large sample sizes. In this paper, we propose an exact test based on Simon's minimax and optimal design criteria originally used in one-arm phase II designs based on binary endpoints. The convergence rate of the joint distribution of the first and second stage test statistics to the limiting distribution is studied, and design parameters are provided for a variety of assumed alternatives. The behavior of the test is also examined in the presence of ties, and the proposed designs are illustrated through application in the planning of a hypercholesterolemia clinical trial. The minimax and optimal two-stage procedures are shown to be preferable as compared with the one-stage procedure because of the associated reduction in expected sample size for given error constraints.     

Impact of safety monitoring on error probabilities of binary efficacy outcome analyses in large phase III group sequential trials

In phase III clinical trials, some adverse events may not be rare or unexpected and can be considered as a primary measure for safety, particularly in trials of life-threatening conditions, such as stroke or traumatic brain injury. In some clinical areas, efficacy endpoints may be highly correlated with safety endpoints, yet the interim efficacy analyses under group sequential designs usually do not consider safety measures formally in the analyses. Furthermore, safety is often statistically monitored more frequently than efficacy measures. Because early termination of a trial in this situation can be triggered by either efficacy or safety, the impact of safety monitoring on the error probabilities of efficacy analyses may be nontrivial if the original design does not take the multiplicity effect into account. We estimate the actual error probabilities for a bivariate binary efficacy-safety response in large confirmatory group sequential trials. The estimated probabilities are verified by Monte Carlo simulation. Our findings suggest that type I error for efficacy analyses decreases as efficacy-safety correlation or between-group difference in the safety event rate increases. In addition, although power for efficacy is robust to misspecification of the efficacy-safety correlation, it decreases dramatically as between-group difference in the safety event rate increases.     

Sample size recalculation for binary data in internal pilot study designs

For binary endpoints, the required sample size depends not only on the known values of significance level, power and clinically relevant difference but also on the overall event rate. However, the overall event rate may vary considerably between studies and, as a consequence, the assumptions made in the planning phase on this nuisance parameter are to a great extent uncertain. The internal pilot study design is an appealing strategy to deal with this problem. Here, the overall event probability is estimated during the ongoing trial based on the pooled data of both treatment groups and, if necessary, the sample size is adjusted accordingly. From a regulatory viewpoint, besides preserving blindness it is required that eventual consequences for the Type I error rate should be explained. We present analytical computations of the actual Type I error rate for the internal pilot study design with binary endpoints and compare them with the actual level of the chi‐square test for the fixed sample size design. A method is given that permits control of the specified significance level for the chi‐square test under blinded sample size recalculation. Furthermore, the properties of the procedure with respect to power and expected sample size are assessed. Throughout the paper, both the situation of equal sample size per group and unequal allocation ratio are considered. The method is illustrated with application to a clinical trial in depression. Copyright © 2004 John Wiley & Sons Ltd.     

临床的思维过程及其特征

运用思维科学的理论 ,将临床解决问题的思维过程 ,相对地界定为发现问题、明确问题、提出假设、检验假设 4个阶段 ,并阐述 4个阶段的思维特征。例举西安医科大学运用大剂量维生素C治疗克山病急性发作的治疗过程 ,使临床思维过程 4个阶段的特征更加明晰     

Alone,together: On the benefits of Bayesian borrowing in a meta-analytic setting

It is common practice to use hierarchical Bayesian model for the informing of a pediatric randomized controlled trial (RCT) by adult data, using a prespecified borrowing fraction parameter (BFP). This implicitly assumes that the BFP is intuitive and corresponds to the degree of similarity between the populations. Generalizing this model to any $K\ge 1$ historical studies, naturally leads to empirical Bayes meta-analysis. In this paper we calculate the Bayesian BFPs and study the factors that drive them. We prove that simultaneous mean squared error reduction relative to an uninformed model is always achievable through application of this model. Power and sample size calculations for a future RCT, designed to be informed by multiple external RCTs, are also provided. Potential applications include inference on treatment efficacy from independent trials involving either heterogeneous patient populations or different therapies from a common class.