熵权法在手术无影灯技术评估中的应用

医疗设备的综合技术评估是其招标采购前的关键环节,必须有一个公正、合理、科学、准确的评价方法。熵权法能够减少人为主观因素的影响,可根据客观参数对产品进行客观评价,保证技术评估的科学性和规范性。本文阐述了熵权法在手术无影灯技术评估中的应用过程。     

肝纤维化的影像学评价（综述）

摘要：肝纤维化的影像学检查在其诊断、鉴别及分期中的作用及优势明显,具有广阔的临床应用前景。本文系统回顾诊断肝纤维化的各种影像检查方法,总结超声、CT及磁共振成像在肝纤维化诊断中的应用及进展,评价各种方法的特点。     

脂肪肝的超声定量诊断研究

对国内外脂肪肝定量诊断方法文献进行分析和归纳,借以评价超声诊断技术在脂肪肝定量诊断中的价值。研究发现超声诊断技术在脂肪肝定量诊断中具有重要的临床应用前景,为临床早期诊断、系统治疗以及疗效评价提供可靠的诊断评估手段。另外,多指标量化体系评价脂肪肝及其程度将是我们今后脂肪肝量化诊断的研究方向。     

CT诊断肾挫裂伤的效果分析

目的 探讨CT诊断在肾挫裂伤患者临床诊疗中的应用效果,评价CT诊断的临床价值.方法 选取我院2018年1月-2021年12月期间收治的疑似52例肾挫裂伤患者作为研究对象,先后接受超声检查和CT诊断,结合超声检查结果和CT诊断结果进行分析,对比手术诊断结果,评价两种诊断方法的应用效果.结果 在52例肾挫裂伤患者的临床诊断...     

CT诊断肾挫裂伤的效果分析

目的 探讨CT诊断在肾挫裂伤患者临床诊疗中的应用效果,评价CT诊断的临床价值。方法 选取我院2018年1月-2021年12月期间收治的疑似52例肾挫裂伤患者作为研究对象,先后接受超声检查和CT诊断,结合超声检查结果和CT诊断结果进行分析,对比手术诊断结果,评价两种诊断方法的应用效果。结果 在52例肾挫裂伤患者的临床诊断中,CT诊断对于疾病诊断特异度、灵敏度和准确度分别为90.00%、95.24%、94.23%,均高于超声检查,其中灵敏度和准确度两种方法之间比较,差异有统计学意义（P<0.05）;且CT诊断结果与手术结果具有非常高的一致性,具有临床使用价值。结论 在肾挫裂伤的临床诊断中,CT诊断方法是一种良好的选择,能够准确检出肾挫裂伤的发生,评估其严重程度,可以为治疗工作提供重要的参考,同时对患者的预后进行判断。     

基于DRGs的熵权TOPSIS和综合指数法在肿瘤科综合评价中的应用

目的 以肿瘤科四个病区2021年绩效指标为例进行综合评价,为医院加强临床专科绩效指标精细化管理,促进学科建设与发展,提升医疗质量提供参考。方法 以医院2021年DRGs指标为基础,应用熵权赋值法确定各评价指标的权重,运用TOPSIS和综合指数法两种综合评价法对肿瘤科四个病区2021年绩效指标进行综合评价。结果 肿瘤科四个病区2021年综合绩效排名依次为肿瘤四、肿瘤二、肿瘤一和肿瘤三。结论 基于DRGs的熵权TOPSIS和综合指数法在肿瘤科综合评价中的应用,能对医院各病区之间的绩效指标进行客观、真实的评价,为医院学科发展、质效评价提供依据。     

经食道心房调搏测定窦房结恢复时间

1972年Mandel应用经静脉右房调搏测定窦房结恢复时间(Sinus Node Recover Time简称SNRT)以估计和评价窦房结功能,但因属侵入性检查,故限制了其临床应用。经食道心房调搏的方法,使SNRT的测定成为非创伤性方法,更利于临床应用。现根据文献并结合我们工作中的体会,讨论食道心房调搏测定SNRT在SSS诊断中的价值。     

肿瘤标记物CA-125在卵巢肿瘤诊断中的临床评价

目的评价血清CA-125在卵巢肿瘤诊断中的临床准确性。方法对108例卵巢肿瘤患者用电化学发光免疫分析法检测其血清CA-125水平,用ROC曲线对其在卵巢肿瘤及卵巢癌诊断中的敏感性和特异性进行评价。结果血清CA-125用于卵巢肿瘤诊断的敏感性为92%,特异性为87%;用于卵巢癌诊断的敏感性为70%,特异性为76%。结论血清CA-125在卵巢肿瘤诊断中有较高的敏感性和特异性,可用于卵巢肿瘤的初筛;而在卵巢癌的诊断时应联合测定其他肿瘤标志物并结合妇科B超、影象学检查等临床检查以提高其临床诊断的准确性。     

64排螺旋CT在颈动脉狭窄中诊断价值

目的:探讨64层螺旋CT在颈动脉狭窄中的影像学表现及诊断价值评价。方法:对我院已确诊存在不同狭窄程度的35例颈动脉狭窄患者进行回顾性分析,研究64层螺旋CT扫描及三维重建资料,并对其进行效果评价。结果:64层螺旋CT对颈动脉狭窄有很高的临床诊断价值。结论:64层螺旋CT血管快捷、方便、检出率高,对颈动脉狭窄的诊断有较高的临床应用价值。     

加乘混合法综合评价大气污染健康效应

本文利用已有资料 ,结合其自身特点 ,选择加乘混合法综合评价大气污染的健康效应 ,并对综合评价方法的优化选择提出一点意见和建议。方　　法1 采用熵值法对指标赋权综合评价是通过多项指标来进行的。如果某指标在这项评价中的分辨信息愈丰富 ,就愈能影响评价结果。在多目标决策理论中 ,信息量的大小用熵来表示。熵值法赋权就是利用指标熵对评价结果的影响力来定权。具体步骤为 :通过“取倒”使逆指标正向化 ;将指标实际值按比重法转化为评价值ｂｉｊ;计算指标 ｊ的熵值ｅｊ=-Σｂｉｊｌｎｂｉｊ;计算指标 ｊ的差异系数 :ｄｊ=1-ｅｊ/ｌｎ(…     

Relative entropy as a measure of diagnostic information.

Relative entropy is a concept within information theory that provides a measure of the distance between two probability distributions. The author proposes that the amount of information gained by performing a diagnostic test can be quantified by calculating the relative entropy between the posttest and pretest probability distributions. This statistic, in essence, quantifies the degree to which the results of a diagnostic test are likely to reduce our surprise upon ultimately learning a patient's diagnosis. A previously proposed measure of diagnostic information that is also based on information theory (pretest entropy minus posttest entropy) has been criticized as failing, in some cases, to agree with our intuitive concept of diagnostic information. The proposed formula passes the tests used to challenge this previous measure.     

The comprehensive diagnostic study is suggested as a design to model the diagnostic process

ObjectivesThe classical diagnostic cross-sectional study has a focus on one disease only. Generalist clinicians, however, are confronted with a wide range of diagnoses. We propose the “comprehensive diagnostic study design” to evaluate diagnostic tests regarding more than one disease outcome.Study Design and SettingWe present the secondary analysis of a data set obtained from patients presenting with chest pain in primary care. Participating clinicians recorded 42 items of the history and physical examination. Diagnostic outcomes were reviewed by an independent panel after 6-month follow-up (n = 710 complete cases). We used Shannon entropy as a measure of uncertainty before and after testing. Four different analytical strategies modeling specific clinical ways of reasoning were evaluated.ResultsAlthough the “global entropy” strategy reduced entropy most, it is unlikely to be of clinical use because of its complexity. “Inductive” and “fixed-set” strategies turned out to be efficient requiring a small amount of data only. The “deductive” procedure resulted in the smallest reduction of entropy.ConclusionWe suggest that the comprehensive diagnostic study design is a feasible and valid option to improve our understanding of the diagnostic process. It is also promising as a justification for clinical recommendations.     

两种DRG绩效评价方法的应用效果比较研究

目的探讨两种DRG绩效评价方法的应用效果。方法一种方法为灰色关联熵权法,它是在DRG指标同质化基础上,结合熵权法和灰色关联度确定各科室DRG绩效值;另一种方法是专家咨询法计算绩效值。对比这两种评价方法的绩效排序。结果两种方法的评价结果呈弱正相关（Kendall秩相关系数为0.333,P＜0.05）,评价结果差异无统计学意义（配对秩和统计量为0.824,P＞0.05）。专家咨询法评价中有16个科室绩效值相同,而灰色关联熵权法评价中未出现科室绩效值相同情况。结论与专家咨询法相比,灰色关联熵权法的评价区分度更高,客观性更强,可为管理决策提供科学有效的依据。     

Sequential evaluation of a medical diagnostic test with binary outcomes

In a study evaluating a medical diagnostic test, human samples are valuable and often costly, therefore prime concerns require termination of the study if the test is evidently inefficient (or efficient) in diagnosis of diseases in order to keep the number of samples as low as possible. In this paper, we propose sequential designs to evaluate the sensitivity and specificity of a diagnostic test. One method allows early stopping if the sensitivity and specificity of a new medical test are both within the level of tolerance. Another method terminates the study if either the sensitivity or the specificity is below the minimally acceptable level. The latter method minimizes the expected sample size when the test does not meet expectations on performance, and illustrates substantial advantage of having smaller expected sample sizes in various two-stage designs compared to the sample sizes of single-stage designs when a diagnostic test is not promising.     

基于信息熵的决策树在慢性胃炎中医辨证中的应用

目的探讨基于信息熵的决策树在慢性胃炎中医辨证分型中的应用.方法对406例慢性胃炎病例进行bootstrap抽样至2000病例,采用基于信息熵的决策树C4.5算法建立中医辨证模型.结果决策树C4.5算法筛选出影响中医辨证分型的26个重要因素;产生可用于分类的诊断规则;建立辨证模型,模型分类符合率为,训练集83.60%,验证集80.67%,测试集81.25%.结论决策树C4.5算法建立的模型效果较好,可应用于慢性胃炎中医辨证分型的预测.     

Meta-analysis of diagnostic tests with imperfect reference standards.

We present a method to estimate the summary receiver operating characteristic (SROC) curve for combining information on a diagnostic test from several different studies. Unlike previous methods that assume the reference standard to be error free, our approach allows for the possibility of errors in the reference standard, through use of a latent class model. The model provides estimates of the sensitivity and specificity of the diagnostic test and the case prevalence in each study; these parameters can then be used in a meta-analysis, for example, using the regression method proposed by Moses et al., of a measure of test discrimination on a measure of the diagnostic threshold, to fit the SROC. The method is illustrated with an example on Pap smears that shows how adjusting for imperfection in the reference standard typically reduces the scatter of data in the SROC plot, and tends to indicate better performance of the test than otherwise.     

A new logistic regression approach for the evaluation of diagnostic test results.

The value of a dichotomous diagnostic test is often described in terms of sensitivity, specificity, and likelihood ratios (LRs). Although it is known that these test characteristics vary between subgroups of patients, they are generally interpreted, on average, without considering information on patient characteristics, such as clinical signs and symptoms, or on previous test results. This article presents a reformulation of the logistic regression model that allows to calculate the LRs of diagnostic test results conditional on these covariates. The proposed method starts with estimating logistic regression models for the prior and posterior odds of disease. The regression model for the prior odds is based on patient characteristics, whereas the regression model for the posterior odds also includes the diagnostic test of interest. Following the Bayes theorem, the authors demontsrate that the regression model for the LR can be derived from taking the differences between the regression coefficients of the 2 models. In a clinical example, they demonstrate that the LRs of positive and negative test results and the sensitivity and specificity of the diagnostic test varied considerably between patients with different risk profiles, even when a constant odds ratio was assumed. The proposed logistic regression approach proves an efficient method to determine the performance of tests at the level of the individual patient risk profile and to examine the effect of patient characteristics on diagnostic test characteristics.     

诊断试验证实偏倚校正方法的比较研究

目的探讨两阶段两分类诊断试验存在证实偏倚时灵敏度和特异度的校正方法并进行比较。方法运用实例和模拟数据说明传统方法灵敏度和特异度的有偏估计,并运用最大似然估计和贝叶斯估计对灵敏度和特异度进行校正。结果传统方法计算的灵敏度和特异度存在偏倚,最大似然法和贝叶斯方法虽然均可校正估计偏倚,但是后者计算的可信区间比前者窄。结论在对诊断试验证实偏倚进行校正时,若有良好的先验信息,贝叶斯方法所获的结果更精确。     

Determination of the efficiency of registration of X-ray diagnostic systems by visually detected minimal radiation contrast

Described in the paper is a relatively simple method for the determination of the efficiency of registration of X-ray diagnostic systems by the whole tract of transformation of radiation contrast from the spot of contrast-sensitivity test to the visual registration of image. It is just enough to have the contrast sensitivity test and to measure the dose at test location. On the basis of the visually registered minimal contrast the efficiency of registration of a diagnostic system is evaluated by the radiation-contrast parameter. The suggested method can be used at handover tests and in testing the X-ray systems during their exploitation.     

科技期刊学术影响力综合评价模型与实证

【目的】探讨单一评价模型和组合评价模型在科技期刊学术影响力综合评价中的适用性,以引起科技期刊对组合评价模型的重视。【方法】运用均方根法、熵值法、主成分分析法和因子分析法对18种科技期刊学术影响力进行评价,对评价结果进行Kendall检验,在此基础上建立模糊Borda组合评价模型对样本进行再评价。【结果】单一评价模型通过了Kendall检验,但从方法适用性上看,因子分析法最佳,主成分分析法次之,熵值法适用性较差,均方根法不太适合用来评价科技期刊学术影响力。模糊Borda组合评价模型具有较强的适用性,其评价结果与国际通用的复合影响因子评价指标较为接近。【结论】对科技期刊评价指标进行客观赋权,运用组合评价模型进行评价能够确保评价结果更为科学可信,提高复合影响因子、复合他引影响因子、复合即年指标、被引期刊数和Web即年下载率是扩大科技期刊学术影响力的有效手段。