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1.
Aims: Depression is the most frequent comorbidity reported among patients with rheumatoid arthritis (RA). Comorbid depression negatively impacts RA patients’ health-related quality-of-life, physical function, mental function, mortality, and experience of pain and symptom severity. The objective of this study was to assess healthcare utilization, expenditures, and work productivity among patients with RA with or without depression.Materials and methods: Data from adult patients who had at least two visits each related to RA and depression over a 1-year period were extracted from the Truven Health MarketScan research databases. Outcomes comprised healthcare resource utilization, work productivity loss, and direct healthcare costs comparing patients with RA with depression (n?=?3,478) vs patients with RA without depression (n?=?43,222).Results: Patients with RA and depression had a significantly greater relative risk of hospitalization and number of all-cause and RA-related hospitalizations, utilization of emergency services, days spent in the hospital, physician visits, and RA-related surgeries compared with RA patients without depression. Patients with RA and depression had a higher risk of and experienced more events and days of short-term disability compared with patients without depression. The incremental adjusted annual all-cause and RA-related direct costs were $8,488 (95% CI = $6,793–$10,223) and $578 (95% CI = –$98–$1,243), respectively, when comparing patients with RA and depression vs RA only.Limitations: The current analysis is subject to the known limitations of retrospective studies based on administrative claims data.Conclusions: This study suggested increased healthcare utilization, work productivity loss, and economic burden among RA patients due to comorbid depression. These findings emphasize the importance of managing depression and including depression as a factor when devising treatment algorithms for patients with RA. 相似文献
2.
组网是卫星、无人机等飞行器集群实现协同的基础。传统自组织组网技术针对地面随机移动场景设计,不适用于拓扑和传输根据任务变化的飞行器集群场景,为此设计了一种管理与任务分离的组网方法,将网络分为管理面和任务面两个逻辑层面,管理面负责拓扑发现、路由建立、任务规划等基础组网功能,任务面负责任务执行过程中的数据传输功能。管理面和任务面实行不同的组网策略,从而使得网络的传输性能根据管理和任务执行的不同需求进行优化,以减少协议开销及降低传输自干扰。 相似文献
3.
张立国 《技术经济与管理研究》2015,(1):125-128
中国经济已经到了只有转型升级才能持续健康发展的关键阶段,产业转型升级在国家政策文件和研究文献中出现的词频较高。文章以我国物流业为研究对象,从现有涉及到物流业转型升级方面的文献挖掘有效信息,梳理我国物流业转型升级研究的历史脉络,从供应链与价值链、产业集群、现代科学技术应用和产业联动四个视角对现有的物流业转型升级文献进行了总结和归纳,并从物流业转型升级的动力研究、阶段性划分研究和演进规律研究三个方面指出了现有文献的研究不足和以后可能的研究方向。其中,供应链与价值链视角侧重于物流企业的纵向角度,产业集群视角侧重于物流企业的横向角度。文章对于物流企业战略设计、政府政策的制定和理论研究具有一定的参考作用。 相似文献
4.
5.
周华林 《全球科技经济瞭望》2008,23(8)
当前,产业集群现象遍布全国各地,是推动区域经济的一股重要力量,分析各产业集群竞争力,已经成为人们争相考虑的一个问题.本文作者认为,产业集群竞争力是产业集群综合实力的反映,应该从产业集群的经济社会形势、集中度指数以及可持续发展情况等方面来分析. 相似文献
6.
徐元旦 《全球科技经济瞭望》2008,23(6):32-36
产业集群的蓬勃发展带动了我国区域经济迅速发展,但当前我国产业集群中企业创新不足的问题日益显现,阻碍了产业集群的进一步发展,而要强化产业集群技术创新,关键是探寻技术创新的实现路径,整合创新要素,做出有利于推进产业集群技术创新的战略选择. 相似文献
7.
Robustness issues in multilevel regression analysis 总被引:8,自引:0,他引:8
A multilevel problem concerns a population with a hierarchical structure. A sample from such a population can be described as a multistage sample. First, a sample of higher level units is drawn (e.g. schools or organizations), and next a sample of the sub‐units from the available units (e.g. pupils in schools or employees in organizations). In such samples, the individual observations are in general not completely independent. Multilevel analysis software accounts for this dependence and in recent years these programs have been widely accepted. Two problems that occur in the practice of multilevel modeling will be discussed. The first problem is the choice of the sample sizes at the different levels. What are sufficient sample sizes for accurate estimation? The second problem is the normality assumption of the level‐2 error distribution. When one wants to conduct tests of significance, the errors need to be normally distributed. What happens when this is not the case? In this paper, simulation studies are used to answer both questions. With respect to the first question, the results show that a small sample size at level two (meaning a sample of 50 or less) leads to biased estimates of the second‐level standard errors. The answer to the second question is that only the standard errors for the random effects at the second level are highly inaccurate if the distributional assumptions concerning the level‐2 errors are not fulfilled. Robust standard errors turn out to be more reliable than the asymptotic standard errors based on maximum likelihood. 相似文献
8.
灰色聚类综合评价方法在住宅建筑方案选优中的应用 总被引:2,自引:2,他引:2
阐述了基于灰色聚类原理开发出的一种综合评价方法,其应用于住宅建筑方案选优,既可选出相对最优方案,又可直观地评出其属于何种等级的灰类。 相似文献
9.
Robert?StewartEmail author Karen?Hill Jessa?Stewart David?Bimler John?Kirkland 《Quality and Quantity》2005,39(6):687-709
The underlying “architecture of the decision to pursue a degree in psychology was quantified using the Method of Sorting technique
to identifying the critical issues necessary to make this choice. Multidimentsional scaling procedures were employed to construct
a three-dimensional map representing the relationships between reasons for selecting psychology as a major. Freshman and senior
psychology majors (N = 165) from a regional university and a large research-based institution rated the relative importance of items in their
decision-making process. Hierarchical clustering procedures revealed seven different groups of students. Although significant
differences associated with class standing were not found, institutional affiliation did influence cluster composition. Reflecting
local emphases, students at the regional institution had a greater interest in Counseling Psychology, whereas those at the
research-based school focused on Clinical Psychology. This semantic map and the associated item clusters arising from psychology
student data provides an empirical basis for, amongst other things, course selection, faculty-initiated program design or
revision, strategic niche marketing, and student retention. 相似文献
10.
基于模糊综合评判的物流运输企业客户群体价值评估 总被引:1,自引:0,他引:1
论述了物流运输企业实施客户群体价值评估的意义,给出了基于模糊综合评判的对现代物流运输企业客户进行价值评价的基本思路。 相似文献