Minimum MSE Weighted Estimator to Make Inferences for a Common Risk Ratio across Sparse Meta-Analysis Data

The paper aims to discuss three interesting issues of statistical inferences for a common risk ratio (RR) in sparse meta-analysis data. Firstly, the conventional log-risk ratio estimator encounters a number of problems when the number of events in the experimental or control group is zero in sparse data of a 2 × 2 table. The adjusted log-risk ratio estimator with the continuity correction points based upon the minimum Bayes risk with respect to the uniform prior density over (0, 1) and the Euclidean loss function is proposed. Secondly, the interest is to find the optimal weights of the pooled estimate that minimize the mean square error (MSE) of subject to the constraint on where , , . Finally, the performance of this minimum MSE weighted estimator adjusted with various values of points is investigated to compare with other popular estimators, such as the Mantel-Haenszel (MH) estimator and the weighted least squares (WLS) estimator (also equivalently known as the inverse-variance weighted estimator) in senses of point estimation and hypothesis testing via simulation studies. The results of estimation illustrate that regardless of the true values of RR, the MH estimator achieves the best performance with the smallest MSE when the study size is rather large and the sample sizes within each study are small. The MSE of WLS estimator and the proposed-weight estimator adjusted by , or , or are close together and they are the best when the sample sizes are moderate to large (and) while the study size is rather small.

Profile Likelihood Tests for Common Risk Ratios in Meta-Analysis Studies

It is well-known that the power of Cochran’s Q test to assess the presence of heterogeneity among treatment effects in a clinical meta-analysis is low due to the small number of studies combined. Two modified tests (PL1, PL2) were proposed by replacing the profile maximum likelihood estimator (PMLE) into the variance formula of logarithm of risk ratio in the standard chi-square test statistic for testing the null common risk ratios across all k studies (i = 1, L, k). The simply naive test (SIM) as another comparative candidate has considerably arisen. The performance of tests in terms of type I error rate under the null hypothesis and power of test under the random effects hypothesis was done via a simulation plan with various combinations of significance levels, numbers of studies, sample sizes in treatment and control arms, and true risk ratios as effect sizes of interest. The results indicated that for moderate to large study sizes (k?≥ 16)?in combination with moderate to large sample sizes?(?≥ 50), three tests (PL1, PL2, and Q) could control type I error rates in almost all situations. Two proposed tests (PL1, PL2) performed best with the highest power when?k?≥ 16?and moderate sample sizes (= 50,100);this finding was very useful to make a recommendation to use them in practical situations. Meanwhile, the standard Q test performed best when?k?≥ 16 and large sample sizes (≥ 500). Moreover, no tests were reasonable for small sample sizes (≤ 10), regardless of study size k. The simply naive test (SIM) is recommended to be adopted with high performance when k = 4 in combination with (≥ 500).

基于LDSCR-at-Risk的PPP项目可融资性评价

通过分析传统的偿债备付率适用性及政府和社会资本合作(PPP)项目的特点,认为传统的偿债备付率不适合于PPP项目可融资性评价。因此,为了评价中长期债务的可融资性,提出了“平准化偿债备付率”(LDSCR),即在借款偿还期内,各年可用于还本付息的资金折现到起始点的现值与贷款金额的比值;进一步提出“风险下的平准化偿债备付率”(LDSCR-at-Risk),即在给定的置信度下的平准化偿债备付率。运用蒙特卡洛仿真进行验证,结果表明:LDSCR-at-Risk可用于PPP项目的可融资性评价,且在可以评价具有风险的PPP项目可融资性的同时,还避免了如何确定项目的最低偿债备付率的问题,从而促进PPP项目融资的发展。

Biomechanical Considerations in the Unruptured Cerebral Aneurysm Study (UCAS Japan): Rupture Risk and True Stress of Wall

When an unruptured aneurysm is found, deciding whether to operate or follow up is one of the most important issues. There are guidelines for making the best final decision on treatment, taking into account the effectiveness of diagnostic and therapeutic devices and the risk-benefit ratio of patients, caregivers, and healthcare professionals. The guidelines evidence-based of large clinical data for this purpose are presented by national medical societies. As one of the rupture risk indicators, there is the hazard risk ratio derived by the UCAS Japan research group based on the statistical method of 6697 aneurysms in 5720 patients with cerebral aneurysms of 3 mm or more. Therefore, we investigated the biomechanical significance of this hazard risk ratio using a spherical aneurysm model. It was revealed that 1) the reason why the frequency of aneurysm rupture is relatively high up to about 10 mm, 2) the UCAS hazard risk ratio corresponds to stress of the aneurysm wall, and the true stress can be calculated by multiplying the patient’s blood pressure, and 3) the factors that cause the daughter’s sac (irregular protrusion of the aneurysm wall). In addition, our two methods for measuring the strength of the blood vessel wall of an individual patient were described.

Optimal Insurance with Background Risk under the Ambiguity and Belief Heterogeneity Structure

In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal insurance contract when maxing the insured’s expected utility of his/her remaining wealth under the smooth ambiguity model and the heterogeneous belief form satisfying the MHR condition. We calculate the insurance premium by using generalized Wang’s premium and also introduce a series of stochastic orders proposed by [1] to describe the relationships among the insurable risk, background risk and ambiguity parameter. We obtain the deductible insurance is the optimal insurance while they meet specific dependence structures.

TyG-BMI、HAR、GRI与糖尿病视网膜病变的关系

目的探讨甘油三酯葡萄糖体重指数(TyG-BMI)、高密度脂蛋白胆固醇与载脂蛋白A比值(HAR)、血糖风险指数(GRI)与糖尿病视网膜病变(DR)的关系。方法将159例2型糖尿病(T2DM)并发DR患者(DR组)根据DR国际临床分级标准分为非增殖期视网膜病变组(NPDR组,66例)和增殖期视网膜病变组(PDR组,93例),另择159例未发生DR的T2DM患者为对照组。记录临床信息和基线实验室检查结果,计算TyG-BMI、HAR、GRI。多因素Logistic回归分析DR发病的影响因素,受试者工作特征(ROC)曲线分析TyG-BMI、HAR、GRI对DR的诊断价值。结果DR组T2DM病程,合并高血压、糖尿病肾病、糖尿病足比例,糖化血红蛋白(HbA1c)、稳态模型胰岛素抵抗指数(HOMA-IR)、总胆固醇(TC)、C反应蛋白(CRP)、TyG-BMI、HAR和GRI水平均高于对照组(P<0.05)。PDR组TyGBMI、HAR和GRI均高于NPDR组(P<0.05)。多因素Logistic回归分析结果显示,T2DM病程较长[OR(95%CI):2.781(1.398~5.534)]、高TyG-BMI[2.036(1.169~3.546)]、高HAR[1.890(1.090~3.280)]、高GRI[1.836(1.065~3.167)]是DR患病的危险因素(P<0.05)。ROC曲线分析结果显示,联合TyG-BMI、HAR、GRI诊断DR的曲线下面积(AUC)高于单独诊断[分别为0.940(0.908~0.964)、0.864(0.821~0.900)、0.796(0.747~0.839)、0.836(0.790~0.875),均P<0.05]。结论T2DM患者TyG-BMI、HAR、GRI增高与DR发病及病情严重程度有关,可用于评估DR的发病风险。

儿童热性惊厥急性期惊厥复发的危险因素分析

目的探讨儿童热性惊厥急性期惊厥复发的相关危险因素。方法收集2021年1月至12月急诊科诊治的热性惊厥(FS)患者,将急性期有惊厥复发者列为热性惊厥复发组(RFS),同期年龄和性别1∶2匹配,急性期无惊厥复发者(NRFS)列为对照组。比较RFS组和NRFS组的人口统计学、惊厥临床特征和实验室资料,将单因素分析有统计学意义的变量进一步纳入多因素条件logistic回归分析,研究儿童FS急性期惊厥复发的危险因素。结果204例患儿中,RFS组68例,NRFS组136例。与NRFS组相比,RFS组患儿具有较短的发热至惊厥潜伏期、较小的FS首发年龄、较低的惊厥发作体温,较高的中性粒细胞-淋巴细胞比值、单核细胞-淋巴细胞比值(MLR)和C反应蛋白(CRP),差异均有统计学意义(P<0.05);经多因素条件logistic回归分析最终得出:阳性FS家族史(OR=8.157,95%CI:2.773~23.989)、首次FS月龄(OR=0.960,95%CI:0.928~0.994)、MLR(OR=6.608,95%CI:1.505~29.020)和CRP(OR=1.108,95%CI:1.041~1.180)是FS急性期惊厥复发的影响因素,其联合预测指标的受试者工作特征(ROC)曲线下面积(AUC)=0.871,95%CI:0.818~0.923,临界值为0.30时,灵敏度为85.3%,特异度为76.5%。结论阳性FS家族史、较小的首次FS月龄、较高的MLR和CRP是儿童热性惊厥急性期惊厥复发的危险因素,运用logistic回归构建联合预测因子,对FS急性期惊厥复发具有较高的诊断价值。

维持性血液透析患者腹主动脉钙化风险预测模型构建

目的研究维持性血液透析(maintenance hemodialysis,MHD)患者血浆致动脉硬化指数(atherogenic index of plasma,AIP)、淋巴细胞与单核细胞比值(lymphocyte/monocyte ratio,LMR)与腹主动脉钙化(abdominal aortic calcification,AAC)的相关性,并构建风险预测模型。方法选取2023年5月1日─2024年4月30日在首都医科大学附属北京潞河医院郎府院区血液净化中心接受MHD治疗的患者。通过单因素及多因素Logistic回归分析来确定ACC的危险因素,建立列线图,并进行内部验证。结果共纳入158例MHD患者,分为AAC组(n=106)和非AAC组(n=52);AAC组的年龄(F=1.325,P<0.001)、校正钙(F=0.343,P=0.016)、AIP(F=8.726,P=0.003)、合并糖尿病(F=9.287,P=0.002)高于非AAC组;透析时长(F=3.681,P=0.007)、血白蛋白(F=3.287,P=0.002)、血磷(F=0.344,P=0.018)、LMR(F=1.824,P=0.022)低于非AAC组。多因素Logistic回归分析发现高龄(OR=1.071,95%CI:1.034~1.108,P<0.001)、合并糖尿病(OR=3.346,95%CI:1.428~7.843,P=0.005)、高AIP(OR=1.176,95%CI:1.041~1.33,P=0.009)、低LMR(OR=0.777,95%CI:0.614~0.983,P=0.036)是MHD患者发生AAC的独立危险因素。绘制列线图,计算C-index为0.834(95%CI:0.769~0.899),说明该列线图模型的区分能力较好。绘制校准曲线,模拟曲线和实际曲线绝对误差为0.029,说明模型具有较强的一致性。结论对于MHD患者来说,高龄、合并糖尿病、高AIP、低LMR是MHD患者发生AAC的独立危险因素。依据年龄、糖尿病、AIP、LMR构建的风险预测模型有很好的预测效能。

Evaluation of Deposit Insurance Fund Adequacy Using Credit Risk Model--An Indian Experience

There are two methods widely used for evaluating the adequacy of Deposit Insurance Fund： （i） Target Reserve Ratio and （ii） Credit Risk Model. Target Reserve Ratio is one of the macro level indicators more often set by Regulatory act on the basis of minimum Deposit Insurance Fund margin safety, Target Reserve Ratio is calculated as the ratio of Deposit Insurance Fund to the value of insured deposits. However, TRR does not take into consideration the level of Deposit Insurance potential liability, the Loss at Given Default （LGD） and the historical trend of default rate prevailing among the insured banks. It does not also consider the present condition of the economy and current scenario of the banking sector. This paper discusses primarily about development of Credit Risk Model for evaluating the Deposit Insurance Fund Adequacy. For this purpose, Econometric Credit Risk Model was developed based on the historical data of bank failures and the associated losses of the last 25 years from 1990-91 to 2014-15. The model assesses various possible factors impacting the Deposit Insurance Fund： Default rate, Deposit growth, Exposures, impact of macro-economic factors like GDP, GDS, Inflation and Interest rate changes, etc. on the Deposit Insurance Fund through econometric modeling. The model evaluates the adequacy of Deposit Insurance Fund under both （i） Normal scenarios where there is no （economic） systemic risk assumed and （ii） Worst case scenario at 1% level of significance using Monte Carlo Simulation. Since the model empirically validates all the critical factors impacting the assets and liabilities associated with Loss at Given Default, the model output can also be used to determine a suitable Target Reserve Ratio and such models are being used in countries like USA, Canada, Hong Kong, and Singapore, etc. （IADI, 2009）. More importantly, the model outputs are quite useful in determining the adequacy of deposit insurance fund which is an effective risk control measure that organization like Deposit Insurance Credit Guarantee Corporation （DICGC） can adopt both under normal economic scenario as well as worst case scenario, ensuring a strong financial safety net for the banking sector in India. The model also assesses the default probability and the Loss at Given Default of different types of banks： commercial banks, rural banks, cooperative banks, foreign banks, etc. A risk based on premium can possibly be determined for each type of banks in India.

基于层次分析法与频率比模型的采空塌陷危险性评价

采空塌陷危险性评价是编制地质灾害防治规划、开展地质灾害防治与监测预警工作的重要依据。本文采用层次分析法与频率比模型相结合构建了采空塌陷危险性评价模型(AHP-PF组合模型)。以沈阳市蒲河-清水矿区为例,考虑了地质条件、地表特征、开采条件等3方面影响因素,选取了第四纪覆盖类型、第四纪松散层厚度、地质构造复杂程度、可采煤层顶板强度指标、煤层倾角、地表沉陷速率、采深采厚比、采空区叠置层数等8个评价指标,利用AHP-PF组合模型计算各指标权重及频率比,最后进行采空塌陷危险性分区。评价结果表明,采空塌陷危险性高区主要集中在采深采厚比小、沉陷速率大及目前仍在开采的区域,该区域是地质灾害防治、搬迁避让的重点区域。

Cancer risk among patients with hereditary muscular dystrophies:a population-based study in Taiwan,1997-2009

Muscular dystrophies(MD) comprise a heterogeneous group of hereditary myopathic diseases.In this group,myotonic MD is associated with an increased cancer risk.However,the cancer risk in other types of MD is unclear.To address this gap in knowledge,we assessed data obtained from the Taiwan Health Insurance Program database.A total of 1,272 patients with MD diagnosed between 1997 and 2009 were enrolled.They were followed up for cancer during the same period by record linkage with the cancer certification in Taiwan.Age-and sex-standardized incidence ratios(SIRs) of overall and site-specific cancers were calculated.For congenital and progressive hereditary MD,there were 685 and 505 cases(males:69.5% and 80.6%),the median ages at diagnosis were 16 and 13 years,and the mean follow-up durations were 7.12 and 5.06 years,respectively.In addition,cancers were developed in 10 patients with congenital MD and 3 patients with progressive hereditary MD.Female MD patients exhibited an increased cancer risk,yielding an SIR of 3.37 [95% confidence interval(CI) = 1.38-8.25] in congenital MD and 2.95(95% CI = 0.95-9.19) in hereditary progressive MD.Site-specific cancer SIRs were not powered to be significantly different.In conclusion,genetic defects in hereditary MD may increase cancer risks in females and a sex difference should be further investigated.

A Problem of Testing Homogeneity Against Order Constraints on Risk Differences

Consider I pairs of independent binomial variates x0i and x1i with corresponding parameters P0i and p1i and sample sizes n0i and n1i for i=1, …,I. Let △i = P1i-P0i be the difference of the two binomial parameters, where △i’s are to be of interest and P0i’s are nuisance parameters. The null hypothesis of homogeneity on the risk difference can be written as

应激性血糖升高比值联合糖化血红蛋白水平对老年急性缺血性脑卒中病人静脉溶栓后出血转化的预测价值

目的 探讨应激性血糖升高比值(SHR)联合HbA1c对老年急性缺血性脑卒中(AIS)病人静脉溶栓后出血转化(HT)的预测价值。方法 纳入2018年6月至2020年12月连云港市第一人民医院和江苏大学附属医院接受重组组织型纤溶酶原激活剂(rt-PA)静脉溶栓AIS老年住院病人共234例,依据急性期内复查CT或MRI结果,将病人分为HT组(n=50)和非HT组(n=184)。收集并比较2组病人临床基线资料。采用多因素Logistic回归分析老年AIS病人rt-PA静脉溶栓后HT的危险因素,应用ROC曲线分析SHR、HbA1c及二者联合预测老年AIS病人rt-PA后HT的价值。结果 2组年龄、溶栓前NIHSS评分、FPG、HbA1c水平,房颤、TOAST分型和梗死大面积比例差异均有统计学意义(P<0.05或P<0.01)。多因素Logistic回归分析结果表明:高水平SHR(OR=39.443,95%CI:1.847~842.343)、HbA1c(OR=1.777,95%CI:1.091~2.859)以及大面积梗死(OR=3.093,95%CI:1.359~7.036)是老年AIS病人rt-PA静脉溶栓后HT的独立危险因素。HbA1c、SHR及二者联合预测老年AIS病人rt-PA静脉溶栓后HT风险的AUC分别为:0.631(95%CI:0.541~0.721)、0.656(95%CI:0.654~0.748)、0.741(95%CI:0.665~0.816)。HbA1c联合SHR预测的AUC显著大于两指标单独预测,差异有统计学意义(P均<0.05)。结论 高水平SHR和HbA1c是老年AIS病人rt-PA静脉溶栓后HT的独立危险因素,两者联合可更好地预测老年AIS病人rt-PA静脉溶栓后HT风险。

Evolution and Risk Factors of Maternal Mortality in Cameroon: A Case Control Study

Background: Maternal mortality is still high in sub-Saharan Africa, especially in Cameroon where more efforts to reduce maternal mortality and provide universal access to reproductive health should be made. This study aims to see the evolution of maternal mortality and identify associated risk factors in Laquintinie hospital in Cameroon. Methods: A manual review of records for 166 maternal deaths (cases) and 322 controls was undertaken using a standard audit form. The sample included pregnant women aged 16 - 46 years admitted at the maternity of Laquintinie Hospital in Douala, Cameroon from January 2017 to December 2022. Software SSPS 3 and Logistic regression analysis were used to analyze data. Results: One hundred and sixty-six (166) maternal deaths were identified during the study period for 14,114 live births, representing a maternal mortality ratio of 1176/100,000 live births. Factors significantly associated with maternal mortality included: young age (15 - 24 years) (aOR 0.11, 95% CI 0.00 - 0.76, p = 0.037), Alcohol intake (aOR 22.79, 95% CI 1.04 - 501.3, p = 0.047), Abortion or ectopic pregnancy (aOR 61.53, 95% CI 1.29 - 2927.3, p = 0.037), having no antenatal visits (aOR 388.3 95% CI 5.6 - 2675.9, p = 0.006), being admitted with hemorrhage (aOR 343.7, 95% CI 16.2 - 7276.0, p ,713.0, 95% CI 128.2 - 5,989,223.3, p CI 0.00 - 0.18, p = 0.016). Conclusion: Despite slight decrease in maternal mortality, early diagnosis of pregnancy and good Antenatal care associated with maternal health education are important factors for reducing maternal mortality. Young women were the most affected. Singles, alcoholics, women with a no or only primary education level, and referred women represented the majority of deceased cases.

非人灵长类动物研究能否得到伦理学辩护?

伦理学研究者的基本工作之一是伦理学辩护。伦理学辩护是通过运用逻辑推理用证据或理由证明已经采取的或建议采取的行动或决策是正确的或合乎伦理的,并可在此基础上,提出政策或法规法律方面的建议。因非人灵长类动物与人类相似,再加上“高保真”观念的影响,所以估计每年有超过10万的非人灵长类动物被用于生物医学研究。但是,越来越多的人认为这种研究不符合伦理,因为非人灵长类动物跟人一样能够敏感地感受到痛苦,而不能从研究中受益。此外,一些研究表明,人与非人灵长类动物在各种组织和基因类别方面的差异性明显超过相似性,这让一些科学家坚持的“高保真”观念遭到质疑。从伦理学角度,之所以反对非人灵长类动物实验,一是风险-受益比、成本-效益比并不理想,非人灵长类动物受到了非常明显、严重且不可逆的伤害;二是非人灵长类动物的感受能力接近于人,拥有接近于人所具有的完全的道德地位和边缘性人格地位,将其囚禁于实验室,并用于自身不能受益的研究,不符合伦理规范。综合来看,人类应该逐渐用符合伦理、对科学实际有益、更实用、可重复以及风险-受益比和成本-效益比理想的模型取代非人灵长类动物研究。在逐渐取代过程中,若必须使用非人灵长类动物,则需进行伦理审查和风险-受益比的评估,并坚持3R原则。

婚姻挤压对初婚年龄的影响

在异性婚姻中,当两性婚龄人口数量出现较大差异时,就可能导致某种性别的人口在婚姻市场上难以找到配偶,表现为婚姻挤压。自20世纪80年代后期以来,中国的出生性别比呈现长时间且较为严重的失衡状态,而这些出生人群于2010年前后陆续开始步入婚姻。与此同时,中国初婚年龄推迟的速度显著加快。近10多年来初婚年龄的加速推迟与高出生性别比队列人口进入婚姻市场的时间基本一致。探讨高出生性别比队列人口进入婚姻市场导致的婚姻挤压在当今中国初婚推迟中所起到的作用,为解释中国初婚年龄加速推迟提供新的视角,具有重要的理论和现实意义。本文基于2010年第六次全国人口普查、2015年全国1%人口抽样调查、2018年中国综合社会调查和2020年第七次全国人口普查微观数据,使用多层生存分析方法匹配宏微观数据,探讨婚姻挤压对个体初婚推迟的影响。将省份作为婚姻市场的单元,检验省级层面婚姻挤压程度对个体初婚年龄的影响。婚姻挤压使用考虑了夫妻年龄差的婚配性别比进行测量。研究发现省级婚姻挤压程度对个体初婚风险具有显著负向影响,即省级婚姻挤压程度越大,个体初婚风险越小、初婚年龄就越大。在其他因素不变的情况下,婚配性别比每上升0.1,个体初婚风险降低38.43%。对婚姻市场整体而言,随着婚配性别比提高,男女双方供需失衡加剧,婚姻失配导致婚姻挤压程度提高,婚姻的可获得性降低,从而使人们进入初婚的时间推迟。婚姻市场性别结构失衡是导致个体初婚推迟的重要因素。基于婚姻挤压对初婚年龄推迟具有显著影响的回归分析结果,可以认为近10多年来中国两性初婚年龄出现加速推迟也受到了婚姻挤压的影响。中国20世纪90年代性别比失衡不断加剧,21世纪初性别比失衡处于高位态势,因此近10多年来的婚姻挤压也在不断加剧,对初婚年龄的加速推迟起到了重要作用。另外,回归模型中包含的诸多个人和省级层面的经济社会变量检验结果也进一步验证了经济社会发展的结构性因素对初婚年龄推迟的作用。

Seismic Site Specific Study for Seismic Microzonation: A Way Forward for Risk Resiliency of Vital Infrastructure in Sikkim, India

Seismic Microzonation comprising study of site specific seismic Microtremor (H/V ratio) is deployed to generate seismological parameters (Peak Frequency, Peak Amplification, Site Vulnerability Index) that may help estimate requisite factors for sound building design codes that can be used to construct risk resilient infrastructures. In this paper the site of Pakyong, Sikkim, India has been investigated by dividing it into three differed zones (Zone 1, Zone II, Zone III). The study area is associated with site amplification factor varying from 1.47 to 11.49 with corresponding frequency variations from 0.5 Hz - 12.5 Hz in which site vulnerability index found varied from 0.2 to 220.6. The anomalous subsurface formation with its high amplification corresponds to the centre of the Pakyong sites having conspicuous trend in NW-SE direction suggesting the existence of geological formations of Chlorite, Phyllite with intercalations of Quartzite beneath the centre of Pakyong site. The risk associated with vulnerability index for different zones maintains its variability as Zone I > Zone II > Zone III, indicating the low vulnerability index values are attributed to compact parts of the sub-surface materials with less amplifications whilst high vulnerability index of the site corresponds to relatively lower strength of the sub-surface materials and soft sediments underlying the Pakyong site which can be used for constructing risk resilient structure by enhancing the stiffness coefficient of the sub-surface by providing plausible engineering solutions for the purpose.

管理者超额积极情绪对企业风险承担的影响研究

选取我国2010-2020年A股非金融上市公司年报作为研究样本,构建管理者超额积极情绪指标,研究管理者超额积极情绪对企业风险承担的影响以及相应的影响机制,并探究股权激励在其中的调节作用。实证研究表明,管理者超额积极情绪能促进企业风险承担;股权激励在其中起到正向调节作用,会促进管理者超额积极情绪对企业风险承担的正向影响。作用机制检验表明,管理者超额积极情绪主要通过增加债务融资和减少融资约束程度促进企业风险承担。进一步分析表明,管理者超额积极情绪对企业风险承担的促进作用在非国有企业、高机构投资者持股比例显著。

财政政策导向、国有企业配合度与债务风险——基于最优杠杆率偏离度的检验

国有企业债务风险问题及“平台化”现象引起社会各界关注。探究政策对国有企业融资决策的影响,有助于政府更有效地制定财政政策,引导国有企业规范融资行为,降低国有企业债务风险。笔者运用企业微观数据和宏观经济数据拟合的最优杠杆率构建杠杆偏离度指标,以“四万亿计划”政策措施为例,深入探讨了政策导向促使国有企业债务风险形成的机理。研究表明,相对于非国有企业,国有企业展现出对财政政策更高的配合度。在扩张性财政政策实施后,国有企业更积极地进行融资活动,导致实际杠杆率高于最优杠杆率。机制分析表明,提高政府补助和降低融资成本是促使国有企业配合的重要原因。异质性分析表明,在政策冲击后原本过度负债的国有企业杠杆偏离度更大,进一步扩大了债务风险;而经营范围与政策内容关联、与政府关系更紧密、市场地位更高的国有企业融资意愿也更强。进一步研究发现,过度负债的国有企业持续融资扩大了债务风险,阻碍了新质生产力发展,而低负债的非国有企业融资后能够显著促进新质生产力提高,体现出更高的资源配置效率。据此,提出引导国有企业稳健经营,优化资金配置效率,精准施策等政策建议。

心房颤动患者华法林抗凝治疗初期发生抗凝过度的影响因素研究

背景心房颤动发病率高,是引起脑卒中、心血管疾病及全因死亡的重要危险因素,而适当的抗凝治疗是预防心房颤动相关性卒中的核心。华法林仍然是目前主要的抗凝药物,但其治疗窗较窄,固定剂量的华法林在治疗初期很容易导致过度或抗凝治疗不足,既往华法林抗凝过度的临床研究较少。目的分析心房颤动患者华法林抗凝治疗初期发生抗凝过度的流行病学和临床特征,并探讨发生抗凝过度的影响因素。方法该研究为单中心回顾性队列研究。纳入2017年1月—2022年12月临沂市人民医院收治的行华法林2.5 mg/d治疗的心房颤动患者552例为研究对象,收集患者临床资料,包括年龄、性别、体质量、心房颤动类型(非瓣膜型/瓣膜型)、合并疾病(高血压、糖尿病、低蛋白血症、转氨酶异常、心力衰竭)、联合用药情况(联合用药数量、联用抗菌药物、联用胺碘酮),收集患者治疗前实验室检查结果,包括血清白蛋白(Alb)、血清肌酐(Scr)、血清丙氨酸氨基转移酶(ALT)及血清天门冬氨酸氨基转移酶(AST)水平,收集患者治疗前国际标准化比值(INR)和用药7 d后INR。根据华法林治疗7 d后INR是否>3.0将患者分为抗凝过度组(INR>3.0,n=122)和未抗凝过度组(INR≤3.0,n=430),比较两组患者资料,并采用单因素及多因素Logistic回归分析探究华法林抗凝治疗初期发生抗凝过度的影响因素。结果抗凝过度组患者年龄,女性、瓣膜型心房颤动、低蛋白血症、转氨酶异常比例,联合用药数量,联用胺碘酮比例,AST高于未抗凝过度组;体质量、高血压比例、糖尿病比例、Alb、ALT低于未抗凝过度组(P<0.05)。多因素Logistic回归分析结果显示,年龄≥65岁(OR=1.954,95%CI=1.243~3.073,P=0.004)、体质量≤63 kg(OR=2.967,95%CI=1.841~4.783,P<0.001)、联合用药数量>5种(OR=1.976,95%CI=1.175~3.323,P=0.010)、Scr≥91μmol/L(OR=2.087,95%CI=1.222~3.561,P=0.007)是心房颤动患者华法林抗凝治疗初期发生抗凝过度的独立危险因素,而糖尿病(OR=0.424,95%CI=0.191~0.939,P=0.034)是心房颤动患者华法林抗凝治疗初期发生抗凝过度的保护因素。结论年龄≥65岁、体质量≤63 kg、联合用药数量>5种、Scr≥91μmol/L可能是心房颤动患者华法林抗凝治疗初期发生抗凝过度的危险因素,而糖尿病可能是心房颤动患者华法林抗凝治疗初期发生抗凝过度的保护因素。对于高龄、低体质量、多种药物联合使用、Scr水平升高的华法林抗凝治疗患者应密切监测INR水平。