Time to abandon small-sample cohort research in health psychology?

Comments on the original article, "Avoidant coping as a predictor of mortality in veterans with end-stage renal disease" by E. J. Wolf and D. L. Mori (see record 2009-06704-009), in which the authors report that among 61 patients with endstage renal disease (ESRD), avoidant coping more than doubled the odds of mortality in multivariable analysis. The authors concluded that evaluating coping style in patients with ESRD would be clinically useful and that interventions targeting avoidant coping should be investigated. In this commentary, the current authors note that Wolf and Mori’s (2009) finding was based on a sample where only 23 patients died over 9 years, and results were evaluated using a Cox regression model with six covariates, a ratio of only 3.8 outcome events per variable—well below recommended thresholds (e.g., Babyak, 2004; Peduzzi et al., 1995). Beyond this, the model did not assess key variables typically included in studies of ESRD outcomes (e.g., transplant status, cardiovascular problems). Wolf and Mori chose to focus on the relationship between avoidant coping and mortality. However, bivariable correlations and confidence intervals reported or generated from data in the article showed that the association between avoidant coping and mortality (r=.28, 95% CI [.03 to .50]) was not significantly stronger than two other correlations that were in the opposite direction of what would have been expected: hypertension with mortality (r=?.39, 95% CI [?.15 to ?.59]) and medication compliance with mortality (r=.16, 95% CI [?.10 to .40]). Oddities of this sort are often encountered in very small datasets and, as a result, stronger evidence must be accrued from larger, more robust samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Avoidant coping as predictor of mortality in veterans with end-stage renal disease": Response to Jewett, Newton, Smith, & Thombs (2010).

Responds to the comments by L. R. Jewett, E. G. Newton, S. Smith, and B. D. Thombs (see record 2010-14873-001) on the current authors' original article, "Avoidant coping as predictor of mortality in veterans with end-stage renal disease" (see record 2009-06704-009). In their commentary, Jewett et al note that oddities often encountered in very small datasets—such as the one used by Wolf and Mori—and, as a result, stronger evidence must be accrued from larger, more robust samples. In this response, Jewett et al acknowledge that theirs is a preliminary study of a small and highly select sample and recognize the limited generalizability of our results. Jewett et al maintain that they do not assert that there should be radical changes in clinical or research programs based on their study results, but instead, suggest that further follow-up would be valuable and that readily available and commonly used assessment and intervention procedures may be appropriate in ameliorating avoidant coping in the endstage renal disease (ESRD) population. At the same time, given the focus on mortality, the risk of doing nothing because the evidence is preliminary far outweighs the minimal costs associated with assessing and addressing avoidant coping, particularly since psychological assessment, including of coping behavior, is part of the standard of practice in this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

网络编码在无线Mesh网络中的研究与实现

Mesh网络沿用了Ad Hoc网络中的路由协议,但Mesh网络节点移动性高,路径的生存周期短,根据无线Mesh网络自身的动态特点进行路由协议的优化成为了研究的热点。COPE编码方案是针对Mesh网络中的单播特性提出的一种新的机会网络编码机制,能够提高网络的吞吐量。通过NS2仿真平台对AODV路由协议添加COPE网络编码方案,仿真结果表明在不同网络条件下,AODV和COPE的结合增加了无线节点的编码机会,使网络的吞吐量得到了有效的提高。     

Implementation of a program to improve the continuity of mental health care through Clergy Outreach and Professional Engagement (C.O.P.E.).

There are over 260,000 religious congregations in the United States. They and their clergy are de facto providers of mental health care. Recent models promoting collaboration between clergy and psychologists advocate that shared religious values underlie effective working relationships. This view may impede collaboration with the majority of psychologists, who are not religious, excluding congregants from needed expertise. The Clergy Outreach and Professional Engagement (C.O.P.E.) model was developed and implemented to facilitate continuity of care across a diversity of caregivers. Handouts based on National Institute of Mental Health prevention science categories and case examples illustrate when and how clergy and clinicians would collaborate. The authors introduce and define the term burden reduction to describe a C.O.P.E. outcome. They consider this clinical work religion inclusive rather than faith based. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于源定向中继的机会网络编码的研究与实现

将源定向中继的思想与机会网络编码结合起来,定义了蝶形结构和链状结构的机会网络编码,并提出一种新的环形结构,大大地降低了网络编码的实现难度,从而使网络编码在无线环境下的应用成了现实。在NS2平台上的仿真结果表明,进行机会网络编码后,吞吐量明显提高,同时具有高能量效率。     

Avoidant coping as a predictor of mortality in veterans with end-stage renal disease.

Objective: The aim of this study was to examine the role of active and avoidant coping strategies in predicting mortality in 61 veterans with end-stage renal disease. Design: Participants completed a self-report measure of coping strategies (The COPE; Carver, Scheier, & Weintraub, 1989) and were interviewed as part of a structured assessment to determine their appropriateness for renal transplant. On average, participants were then followed for 9 years via medical record review to determine mortality status. Main Outcome Measures: Mortality, as predicted by factor scores on active and avoidant coping factors estimated via confirmatory factor analysis of select COPE subscales. Results: A Cox regression revealed that a unit change in avoidant coping was associated with a 114% increase in odds of mortality, even after controlling for variance attributable to demographic variables. There was also a statistical trend indicating that this association might be mediated by poor attendance at medical appointments. Active coping did not predict mortality. Conclusion: Results demonstrate the importance of assessing coping style in this population; clinical implications of these findings and possible mechanisms of this effect are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

富氧硫磺回收工艺技术的开发与应用

富氧硫磺回收工艺是指以氧气或富氧空气代替空气增加装置处理量的一系列新型克劳斯工艺,从1985年COPE工艺首次投入工业应用以来已有30年发展历史。根据富氧空气中氧浓度的不同可以分为3种类型:低浓度富氧工艺(氧摩尔分数不超过28%)、中等浓度富氧工艺(氧摩尔分数不超过50%)与高浓度富氧工艺(氧摩尔分数从50%~接近100%)。在进行工程设计时,应按原料酸气中H_2S浓度、需分解的杂质及其浓度等原始数据选择适合的工艺。由于富氧燃烧很容易使燃烧炉达到1 400℃以上的高温,故燃烧器选型、耐火材料选择、氧浓度确定及炉温控制系统设计等皆为该工艺的设计要点。目前,我国大量加工含硫原油,煤制油与煤化工也正在蓬勃发展之中,随着GB 31570-2015《石油炼制工业污染物排放标准》的发布与实施,富氧硫磺回收工艺将会有良好的发展前景,应给予充分重视。