Cost comparison of continued anticoagulation with rivaroxaban versus placebo based on the 1-year EINSTEIN-Extension trial efficacy and safety results

Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI]?=?–$1,454 [–$2,396, $1,231]).

Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment.     

Psychometric validation of anti-clot treatment scale and treatment satisfaction questionnaire for medication version II in Japanese patients with atrial fibrillation

Aims: The Anti-Clot Treatment Scale (ACTS) and Treatment Satisfaction Questionnaire for Medication version II (TSQM-II) are validated treatment satisfaction patient-reported outcome (PRO) instruments. The ACTS includes two domains: Burdens and Benefits; the TSQM-II includes four: Effectiveness, Side Effects, Convenience, and Global Satisfaction. Japanese-language versions of the ACTS and TSQM-II have been developed and linguistically validated. This study aimed to assess their psychometric properties in Japanese patients with atrial fibrillation (AF).

Materials and methods: ACTS and TSQM-II data from 534 patients with AF were collected in a Japanese post-marketing surveillance study of a direct oral-anticoagulant, rivaroxaban. Four key psychometric properties, in line with best practice guidelines from the US Food and Drug Administration, were examined using traditional psychometric methods: acceptability, scaling assumptions, reliability (i.e. internal consistency reliability, test-retest reliability), and construct validity (i.e. convergent validity and known groups).

Results: ACTS Burdens and Benefits and TSQM-II Effectiveness, Convenience, and Global Satisfaction scales were found to be acceptable (e.g. item-level missing data at baseline <4%), with all scales having good internal consistency (Cronbach’s alpha > 0.80). test-retest reproducibility intraclass correlation coefficients for the ACTS Burdens and Benefits were 0.59 and 0.65, respectively, and between 0.54–0.61 for the TSQM-II scales. Known-groups validity for the ACTS and TSQM-II was supported by differences in scale scores by positive and negative impact (p?<?0.05). Correlations between the ACTS and TSQM-II (convergent validity) were lower than expected (range r?=?0.09–0.48), but in line with the original ACTS development study.

Limitations: Evaluation of test-retest reproducibility was limited by assessment period, which was longer (3 months) than recommended guidelines (usually up to 2 weeks).

Conclusions: Overall, Japanese versions of ACTS and TSQM-II scales satisfied internal consistency reliability and traditional validity criteria. Our study supports the ACTS and TSQM-II as appropriate PRO instruments to measure satisfaction with anticoagulant treatment in Japanese patients with AF.

Trial registration: NCT01598051, clinicaltrials.gov; registered April 20, 2012.     

采油污水处理工艺探讨

针对采油污水的水质特点,以及其中有机污染物的组成,结合现有处理工艺,确定了以生化法降解有机污染物为核心的处理工艺,实现了达标排放,并对处理工艺适用性进行了分析。     

运行电站爆破震动控制研究

结合大渡河龚咀水电站下游河床整治爆破开挖拓宽，重点研究了爆破震动对运行电站机组及其仪表的影响，探讨了爆破震动安全判据和控制标准，用了若干实际工程采用的经验指标进行对比分析，所得结论意见可供同类工程作为爆震安全控制参考。     

Design Methodology and Area Sensitivity Analysis of Horizontal Subsurface Flow Constructed Wetlands

An approach is presented to satisfy the demand for simple criteria, guidelines and models for the preliminary sizing of horizontal subsurface flow (SF) constructed wetland systems. This approach eliminates time-consuming calculations and iterations by providing graphical solutions for wetland system sizing. Therefore, it can be used for the preliminary assessment of new or performance evaluation of existing subsurface flow constructed wetland systems. The validity of this methodology is checked with data from existing systems and is found to be quite satisfactory. This methodology is combined with simple equations predicting the maximum wetland capacity in summer, so as to assist designers in sizing installations in tourist areas with increased summer populations. Furthermore, based on this methodology, a sensitivity analysis is performed of the area requirements for wastewaters of various strengths and various design conditions and performance criteria. The results provide a useful overview to engineers and further simplify the design methodology of new subsurface flow constructed wetland systems.     

温州市龙湾段标准堤工程软土地基变形原位观测

温州市龙湾段标准堤地基土中普遍存在一层海积淤泥,其强度低,压缩性高,承载力低,不能满足标准堤填筑及水闸运行的要求。采用预压法进行地基处理,取得的地基沉降、水平位移、孔隙水压力等现场观测资料,总结分析了该段海积淤泥地基的变形规律和特点。并提供了有关的原型观测数据,其沉降曲线规律性较好。     

牛头山水电站混凝土双曲拱坝设计和水库提前蓄水研究

牛头山水电站大坝为抛物线形混凝土双曲拱坝,最大坝高108.0 m,采用坝顶5孔开敞式溢洪道泄洪,挑流消能。为提前发挥水电站效益,在拱坝尚未完全封拱的情况下,通过计算分析,得出了水库可以下闸蓄水的结论。     

葛洲坝二江电厂监控系统升级改造的实施与探讨

葛洲坝二江电厂计算机监控系统投产于1995年,运行时间已久,无论从硬件还是软件方面已不能满足目前的生产要求。升级后的新系统在各个方面均有了很大程度的改进,它的应用使得葛洲坝二江电厂的自动化控制程度有了很大的提高,为厂站“无人值班(少人值守)”的现代化管理以及三峡—葛洲坝梯级电站的联合调度提供了有力的保障。     

抽水蓄能电站运行方式和电网经济效益分析

用计算机模拟法建立模拟模型，对选定的系统进行生产模拟，统计计算出电网系统投入不同抽水蓄能容量时所发生的系统运行总燃料费用（包括抽水蓄能电站的抽水费）和系统的负荷缺电力时间概率（LOLP）等指标。通过对计算结果的分析，得出不同系统在投入不同容量抽水蓄能机组和采取不同运行方式的情况下，其运行总燃料费用的边际成本和LOLP的边际值的变化规律，并且对电网的经济效益进行合理分析。从而为抽水蓄能电站的规划和投资建设提供理论依据，推动抽水蓄能电站的发展，促使我国电源结构趋向合理。     

黄河下游游荡性河道整治方案研究

小浪底水库投入运用后，黄河下游水沙条件的变化，使游荡性河道整治出现了新情况，新问题。下一步治理应注意积极修建新布点工程，完成具有关键性导流作用的续建工程，确定适应新情况的设计治导线，积极开展新结构试验和观测研究。