The postmodernist war on evidence-based practice

In this paper, we examine the war of words between those who contend that health care practice, including nursing, should primarily be informed by research (the evidence-based practice movement), and those who argue that there should be no restrictions on the sources of knowledge used by practitioners (the postmodernists). We review the postmodernist interventions of Dave Holmes and his colleagues, observing that the postmodernist style to which they adhere, which includes the use of continental philosophy, metaphors, and acerbic delivery, tends to obscure their substantive arguments. The heated nature of some responses to them has tended to have the same effect. However, the substantive arguments are important. Five main postmodernist charges are identified and discussed. The first argument, that the notion of ‘best evidence’ implies a hierarchical and exclusivist approach to knowledge, is persuasive. However, the contention that this hierarchy is maintained by the combined pressures of capitalism and vested interests within academia and the health services, is less well founded. Nevertheless, postmodernist contentions that the hierarchy embraced by the evidence-based practice movement damages health care because it excludes other forms of evidence that are needed to understand the complexity of care, it marginalizes important aspects of clinical knowledge, and it fails to take account of individuals or their experience, are all seen to be of some merit. However, we do not share the postmodernist conclusion that this adds up to a fascist order. Instead, we characterize evidence-based practice as a necessary but not sufficient component of health care knowledge.     

From the Cover: Bandit solutions provide unified ethical models for randomized clinical trials and comparative effectiveness research

As electronic medical records enable increasingly ambitious studies of treatment outcomes, ethical issues previously important only to limited clinical trials become relevant to unlimited whole populations. For randomized clinical trials, adaptive assignment strategies are known to expose substantially fewer patients to avoidable treatment failures than strategies with fixed assignments (e.g., equal sample sizes). An idealized adaptive case—the two-armed Bernoulli bandit problem—can be exactly optimized for a variety of ethically motivated cost functions that embody principles of duty-to-patient, but the solutions have been thought computationally infeasible when the numbers of patients in the study (the “horizon”) is large. We report numerical experiments that yield a heuristic approximation that applies even to very large horizons, and we propose a near-optimal strategy that remains valid even when the horizon is unknown or unbounded, thus applicable to comparative effectiveness studies on large populations or to standard-of-care recommendations. For the case in which the economic cost of treatment is a parameter, we give a heuristic, near-optimal strategy for determining the superior treatment (whether more or less costly) while minimizing resources wasted on any inferior, more expensive, treatment. Key features of our heuristics can be generalized to more complicated protocols.     

User-designed information tools to support communication and care coordination in a trauma hospital

BackgroundIn response to inherent inadequacies in health information technologies, clinicians create their own tools for managing their information needs. Little is known about these clinician-designed information tools. With greater appreciation for why clinicians resort to these tools, health information technology designers can develop systems that better meet clinicians’ needs and that can also support clinicians in design and use of their own information tools.ObjectiveTo describe the design characteristics and use of a clinician-designed information tool in supporting information transfer and care coordinationDesignObservations, semi-structured interviews, and photographing were used to collect data. Participants were six nurse coordinators in a high-volume trauma hospital. Content analysis was carried out and interactions with information tools were analyzed.ResultsNurse coordinators used a paper-based information tool (a nurse coordinator’s clipboard) that consisted of the compilation of essential data from disparate information sources. The tool was assembled twice daily through (1) selecting and formatting key data from multiple information systems (such as the unit census and the EHR), (2) data reduction (e.g., by cutting and whitening out non-essential items from the print-outs of computerized information systems), (3) bundling (e.g., organizing pieces of information and taping them to each other), and (4) annotating (e.g., through the use of colored highlighters and shorthand symbols). It took nurse coordinators an average of 41 min to assemble the clipboard. The design goals articulated by nurse coordinators to fit the tool into their tasks included (1) making information compatible with the mobile nature of their work, (2) enabling rapid information access and note-taking under time pressure, and (3) supporting rapid information processing and attention management through the effective use of layout design, shorthand symbols, and color-coding.ConclusionsClinicians design their own information tools based on the existing health information technologies to meet their information needs. The characteristics of these clinician-designed tools provide insights into the “realities” of how clinicians work with health information technologies. The findings suggest an often overlooked role for health information technologies: facilitating user creation of information tools that will best meet their needs.     

Methodological Challenges in Online Trials

Health care and health care services are increasingly being delivered over the Internet. There is a strong argument that interventions delivered online should also be evaluated online to maximize the trial’s external validity. Conducting a trial online can help reduce research costs and improve some aspects of internal validity. To date, there are relatively few trials of health interventions that have been conducted entirely online. In this paper we describe the major methodological issues that arise in trials (recruitment, randomization, fidelity of the intervention, retention, and data quality), consider how the online context affects these issues, and use our experience of one online trial evaluating an intervention to help hazardous drinkers drink less (DownYourDrink) to illustrate potential solutions. Further work is needed to develop online trial methodology.     

Tailoring Interventions: Understanding Medical Practice Culture

This article describes the results of a study that used intensive direct observations of eight medical practices to assess the factors affecting the barriers and facilitators to adult immunization for influenza and pneumonia. The study aimed to describe the culture of these practices by identifying key features that facilitate or deter the immunization process. The article presents profiles of six of the eight practices describing their cultural and organizational frameworks. Six features that are critical to an understanding of the cultures of these practices, particularly as they relate to receptivity to influenza immunization for diverse practices and patient populations, are highlighted. These include policies and procedures, funding source, physician philosophy, patient receptivity to provider recommendation, and physical environment and social environment. The article also discusses strategies for applying knowledge about the culture of each practice to introduce appropriate and feasible interventions aimed at increasing immunization rates.     

儿童先天性心脏病室间隔缺损致病因素分析

目的 :对儿童先天性室间隔缺损因素进行分析。方法 :报告 2 5 8例先天性室间隔缺损儿童 ,男性 14 4例 ,女性 114例 ,年龄 1～ 14岁。同时对 2 5 8例儿童的父母进行调查 ,调查对象为患先天性室间隔缺损儿童 ,儿童的父亲、母亲孕前和孕期多方面因素 ,将引起室间隔缺损的可能原因进行分析。结果 :发现家族中有遗传史 ,父母亲饮酒史 ,母孕期有感冒病史 ,母孕期服用抗病毒药物 ,父母孕期使用黄体酮及母孕期接触X射线 ,有较高先天性室间隔缺损的发病率。同时对患先天性室间隔缺损儿童血型分析 ,表明A型儿童和AB型儿童患先天性室间隔缺损频率较高 (分别为 4 2 2 5 %和 11 2 4 % )比值比(OR)分别为 1 6 3和 2 2 1。与对照组比较差异有显著性 (即A型 χ2 =7.0 2 ,P <0 0 0 1,AB型 χ2 =5 71,P <0 .0 5 )。A O ,AB O抗原患者组与对照组比较 ,OR分别为 1 72和 2 6 2 ,χ2 值分别为 6 72和 7 5 1均差异有显著性 (P <0 .0 0 1) ,而O型则相反患先天性室间隔缺损的机率相对减少。结论 :先天性室间隔缺损与家族遗传史、血型及父母孕期饮酒、服药等多方面因素有关。     

Reasons for drinking less and their relationship to sustained remission from problem drinking

AIMS: To compare representative general population and treated samples on their reasons for drinking less and whether particular reasons were related to sustained remission from problem drinking for either group. PARTICIPANTS AND DESIGN: A total of 659 problem drinking adults in a Northern California county identified through a probability survey in the general population (n = 239) and a survey of consecutive admissions to public and private alcohol and drug programs (n = 420), who reported drinking less at the one-year follow-up and provided reasons for reducing their drinking, were assessed 1-, 3-, and 5-years post-baseline regarding their problem drinking status. MEASUREMENTS: Logistic regression models were used to predict sustained remission from problem drinking. RESULTS: While the treated sample endorsed a majority of reasons in significantly higher proportions than the general population sample, the same three reasons were significant for both groups in predicting sustained remission from problem drinking: hitting rock bottom, experiencing a traumatic event and undergoing a spiritual awakening. Interventions by medical personnel and family members were either non-significant predictors or significantly negatively related to sustained improvement for both general population and treated problem drinkers. CONCLUSIONS: General population and treatment samples have similar reasons for cutting down as they relate to sustained remission from problem drinking.     

Usefulness of a state-legislated,comparative database to evaluate quality in colorectal surgery

PURPOSE: Colorectal surgery, a high-volume procedure, has been targeted for performance improvement to reduce length of stay. Specific postoperative quality indicators and readmission rates should be analyzed concomitantly to assure that adverse events are not associated with earlier discharge. METHODS: From July 1, 1990, to June 30, 1997, 1,218 consecutive patients who underwent transabdominal colorectal surgery were analyzed for length of stay, mortality, morbidity, and discharge disposition. Each patient was assigned an Admission Severity Group rating 0 to 4 using a hospital-based state-legislated software system (Atlas) to validate comparative performance internally and externally. Readmission data within 120 days of discharge were available for the last 678 consecutive patients from July 1, 1993, to June 30, 1997, using Lastword (computerized medical records). RESULTS: The annual frequencies of the 1,218 procedures were 173, 183, 175, 146, 167, 189, and 185, respectively, from July 1990 through June 1997. Severity distribution was 32 for Admission Severity Group 0, 517 for Admission Severity Group 1, 540 for Admission Severity Group 2, 128 for Admission Severity Group 3, and 1 for Admission Severity Group 4, with no annual difference (P=0.012). There was a significant reduction in total length of stay of 3.1 (12.9–9.8) days during the seven years (P=0.001). The overall operative mortality rate was 1.4 percent, and the morbidity was 2.6 percent, with no annual differences (P=0.655 andP=0.033, respectively). The disposition to home did not change (P=0.21). Of the 678 patients followed up for readmission, 100 (14.7 percent) were readmitted within 120 days, with no annual difference (P=0.302). CONCLUSION: Mortality, morbidity, disposition, and readmission rates were not affected by a decreased length of stay after colorectal surgery.Presented at the Research Forum at the meeting of The American Society of Colon and Rectal Surgeons, San Antonio, Texas, May 2 to 7, 1998.     

中药对神经氧化应激损伤保护作用的机制研究

中药有效成分具有增强细胞内超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶等活性、抑制活性氧化物、丙二醛、乳酸脱氢酶等释放,通过清除自由基、抑制脂质过氧化氢和调节抗氧化酶的水平等发挥神经保护作用,其参与的保护效应主要是立足于抗氧化、抑制细胞毒性和抗细胞凋亡等机制,从而预防由活性氧化物堆积引发的中枢神经系统氧化应激损伤。由此,在今后的研究和探索中,更应该注重体内体外实验联合研究,在体外探索药物作用具体靶点,检测其在体内代谢途径和周期,早期干预抗氧化生物标志物,以便准确判断治疗剂量及治疗效果,从而全方位评估中药在宏观上对机体神经系统损伤的调控作用,更深一步研究其发挥疗效的机制。