• Two-thirds of methodological research remained unpublished after presentation at Cochrane Colloquia: an empirical analysis.

    12 December 2017

    OBJECTIVES: To determine the extent to which abstracts of methodology research, initially presented at annual meetings of The Cochrane Collaboration, have been published as full reports and over what period of time. A secondary aim was to explore whether full publication varied in different methodological subject areas. STUDY DESIGN AND SETTING: The Cochrane Methodology Register (CMR) was searched for all abstracts reporting methodology research, presented at the 11 Cochrane Colloquia from 1997 to 2007. EMBASE, PubMed, and CMR were searched for full publications of the same research. RESULTS: We identified 908 eligible conference abstracts and found full publications for 312 (34.4%) of these, almost half of which (47.1%) had appeared by the end of the first year after the relevant Colloquium. The proportion of abstracts that had not been published by 3 years was 69.7%, falling to 66.2% at 5 years. Publication varied considerably between different methodological areas. CONCLUSION: Approximately two-thirds of methodological research studies presented at Cochrane Colloquia remain unpublished as full papers at least 5 years later. This highlights the importance of searching conference abstracts if one wishes to find as comprehensive and complete a sample of methodological research as possible.

  • Visualization studies on evidence-based medicine domain knowledge (series 1): mapping of evidence-based medicine research subjects.

    5 February 2018

    OBJECTIVE: To use visualization methods to illustrate and compare major subjects, domains, and developments in evidence-based medicine (EBM) in recent years. METHOD: We analyzed MeSH terms and keywords in EBM articles in the MEDLINE and CNKI databases, and developed subject charts, research field relationship charts, and strategy coordination charts using word co-occurrence, PFNET algorithms, and visualization methods. RESULT: Rapid developments and growth are taking place in EBM in China and around the world. Studies on humans comprised 94.4% of the EBM studies that we identified, while animal studies accounted for 2.6% (three quarters of these animal studies were on primates). The six countries with the largest number of EBM articles and the eight host nations for the 108 journals with the most EBM publications were from high-income countries. In China, 31 provinces, municipalities, and autonomous regions have published EBM articles, although most of these publications come from the more highly-developed areas of the country. The investigation of word co-occurrence showed that EBM articles outside of China involve seven main fields: "Therapy", "Methods", "Standards", "Research", "Education", "Nursing" and "Organization and Administration". Five of these fields ("Therapy", "Nursing", "Research", "Education" and "Management") were common to China but the top seven fields for this country included "Traditional Chinese Medicine (TCM)" and "Information resources"; and did not include "Methods" and "Standards". Furthermore, studies on "Nursing" and "Research" were not as advanced in China as in other countries. CONCLUSION: There are similarities between China and the rest of the world in several areas in the EBM literature but also some important differences. Throughout the world, the most resource-rich regions o organizations tend to have the most well-developed EBM. These regions and organizations are pdocuing more evidence and conducting more methodology research than the less resourced regions and organizations. There is an urgent need for these regions and organizations to strengthen their use of evidence, to learn more about the philosophy that underpins EBM, and to improve accessibility to, and use of, evidence in choices about health care.

  • Visualization studies on evidence-based medicine domain knowledge (series 2): structural diagrams of author networks.

    14 February 2018

    OBJECTIVE: To investigate the output of evidence-based medicine (EBM) researchers in China and elsewhere by examining the EBM domains they work within and the networks that exist among them; using visualization methods to analyze these relationships. This maps the current situation and helps with the identification of areas for future growth. METHODS: We used co-citation matrixes with Pathfinder networks and hierarchical clustering algorithms, and constructed a co-author matrix which were analyzed with a whole network approach. The analyzed matrixes were visualized with the UCINET program. RESULTS: Much of the development of EBM has been centered around three authors, David Sackett, Gordon Guyatt and L Manchikanti, within three different clusters. The main authors of EBM articles in China were divided into nine academic domains. The relations among core authors of articles indexed by the Science Citation Index (SCI) was loose. There was a stronger co-authorship network among core authors in the Chinese literature, with three groups and 21 cliques. Nine distinct academic communities appeared to have formed around Li Youping, Liu Ming and Zhang Mingming. CONCLUSION: The EBM literature contains several key clusters, with universities in high-income countries being the source of the majority of articles. Outside China, McMaster University in Canada, the original home of EBM, is the dominant producer of EBM publications. In China, Sichuan University is the main source of EBM publications. The EBM cooperation network in China is comprised of three major groups, the largest and most productive in this sample is led by Li Youping with Liu Ming, Zhang Mingming, Li Jing, Wang Li, Wu Taixiang, and Liu Guanjian as central members.

  • Visualization studies on evidence-based medicine domain knowledge (series 3): visualization for dissemination of evidence based medicine information.

    14 February 2018

    PURPOSE: To identify patterns in information sharing between a series of Chinese evidence based medicine (EBM) journals and the Cochrane Database of Systematic Reviews, to determine key evidence dissemination areas for EBM and to provide a scientific basis for improving the dissemination of EBM research. METHOD: Data were collected on citing and cited from the Chinese Journal of Evidence-Based Medicine (CJEBM), Journal of Evidence-Based Medicine (JEBMc), Chinese Journal of Evidence Based Pediatrics (CJEBP), and the Cochrane Database of Systematic Reviews (CDSR). Relationships between citations were visualized. High-frequency key words from these sources were identified, to build a word co-occurrence matrix and to map research subjects. RESULT: CDSR contains a large collection of information of relevance to EBM and its contents are widely cited across many journals, suggesting a well-developed citation environment. The content and citation of the Chinese journals have been increasing in recent years. However, their citation environments are much less developed, and there is a wide variation in the breadth and strength of their knowledge communication, with the ranking from highest to lowest being CJEBM, JEBMc and CJEBP. The content of CDSR is almost exclusively Cochrane intervention reviews examining the effects of healthcare interventions, so it's contribution to EBM is mostly in disease control and treatment. On the other hand, the Chinese journals on evidence-based medicine and practice focused more on areas such as education and research, design and quality of clinical trials, evidence based policymaking, evidence based clinical practice, tumor treatment, and pediatrics. CONCLUSION: Knowledge and findings of EBM are widely communicated and disseminated. However, citation environments and range of knowledge communication differ greatly between the journals examined in this study. This finds that Chinese EBM has focused mainly on clinical medicine, Traditional Chinese Medicine, pediatrics, tumor treatment, nursing, health economic and management, and medical education. Internationally, EBM research topics have begun to shift, from drug treatment to surgery or other non-pharmacological treatments; from therapy to diagnosis, rehabilitation, and prevention; from evidence based clinical practice to evidence based management and policymaking. The philosophy and method of EBM, evidence production and translation are also shifting from well resourced settings to low- and middle-income countries, especially those in which English is not a major language.

  • Effectiveness of gerontologically informed nursing assessment and referral interventions for older persons attending the emergency department: systematic review.

    26 April 2018

    AIM: This paper is a report of a literature review conducted to analyse data from published studies reporting nursing interventions targeted at older attendees of emergency departments (EDs), and to provide a critical appraisal of the evidence concerning their effectiveness. BACKGROUND: Attendance at hospital EDs by older persons presents opportunities for targeted interventions to address actual and potential problems associated with or in addition to the presenting problem. The evidence concerning the effectiveness of such interventions is mixed. DATA SOURCES: Studies were retrieved from a systematic search of published works indexed in CINAHL, MEDLINE (PubMed), Science Direct and the Cochrane Central Register of Controlled Trials (CENTRAL). METHODS: A systematic review of effectiveness was conducted using the Cochrane Effective Practice and Organisation of Care guidelines and a narrative synthesis approach for data handling and presentation. The review period was 1992 to 31 August 2008. RESULTS: Nursing assessment and referral interventions have demonstrated effectiveness in reducing service use and improving physical function, but have failed to demonstrate statistically significant effects on predicted patient and/or health systems outcomes. CONCLUSION: The evidence of the effectiveness of gerontologically informed nursing assessment and referral interventions in EDs must be accepted with caution, as not all studies demonstrated effectiveness in predicted patient and/or health systems outcomes, and the testing of complex social interventions in randomized clinical trials is inherently problematic. Further evidence of the effectiveness of nursing interventions is required, and such evidence might be usefully demonstrated using pragmatic, as opposed to explanatory, trials.

  • DICE 2: a further investigation of the effects of chance in life, death and subgroup analyses.

    3 April 2018

    In an investigation into how chance might influence the distribution of deaths in a randomised trial and the time of those deaths, and to highlight the possible dangers of subgroup analyses, 100 randomised controlled trials were simulated and 50 subgroup pairs were simulated for some of these trials. Each of 580 control patients from a colorectal cancer trial was randomly coded to simulate allocation to treatment or control, the main outcome measure being time to death. Not surprisingly, most of the 100 trials gave non-significant results. Four were conventionally significant with logrank 2p-values of less than 0.05. The most extreme result was associated with a logrank 2p-value of 0.003, showing an absolute reduction in four-year mortality of 40% (SD 15) for patients allocated to treatment. One of the simulated prognostic factors for this trial (subgroup 13) showed that mortality for one type of patient was non-significantly slightly increased by treatment, whereas treatment reduced four-year mortality by 64% (SD 16) among the other patients in the trial (2p = 0.00006). Similar, extreme results were found for a trial of borderline statistical significance overall. Chance can influence the overall results of any randomised controlled trial, regardless of how well it is conducted, and can play an even more powerful role in the results of subgroup analyses. This should be borne in mind both by trialists when reporting their results and by readers and reviewers of those reports.

  • Suicides by opium and its derivatives, in England and Wales, 1850-1950.

    12 December 2017

    In the mid-nineteenth century opium and its derivatives, such as laudanum and morphine, were the most common poisons in suicides in England and Wales. With legislative restrictions on these 'dangerous drugs' such a use declined. This study attempts to show this trend and indicates the large variety of these opium-related suicides.

  • Optimal evidence in difficult settings: improving health interventions and decision making in disasters.

    26 April 2018

    Martin Gerdin and colleagues argue that disaster health interventions and decision-making can benefit from an evidence-based approach Please see later in the article for the Editors' Summary.

  • Treating pneumonia in critical care in the United Kingdom following failure of initial antibiotic: a cost-utility analysis comparing meropenem with piperacillin/tazobactam.

    12 December 2017

    BACKGROUND: Treating patients admitted to critical care with severe pneumonia requires timely intervention with an effective antibiotic. This reduces the risk of dying of pneumonia and minimises complications associated with a prolonged stay in critical care. OBJECTIVE: To compare the cost-effectiveness of meropenem 1 g/8 h with piperacillin/tazobactam 4.5 g/8 h for treating pneumonia in UK critical care. METHODS: A Markov model was built to estimate lifetime costs and quality-adjusted life years (QALYs) of using meropenem versus piperacillin/tazobactam to treat severe pneumonia. Estimates of effectiveness, utility weights and costs were obtained from published sources. Probabilistic sensitivity analysis was conducted to address uncertainty in the model results. RESULTS: Cost of treating a patient with severe pneumonia was estimated as £19,026 with meropenem and £19,978 with piperacillin/tazobactam, respectively. QALYs gained were 4.768 with meropenem and 4.654 with piperacillin/tazobactam. Probabilistic sensitivity analysis showed meropenem to be consistently less costly and more effective than piperacillin/tazobactam. CONCLUSION: The additional efficacy of meropenem translates into more patients surviving critical care and leaving this high-cost service more quickly than if they had been treated with piperacillin/tazobactam. As meropenem is more effective and less expensive than piperacillin/tazobactam at treating patients with severe pneumonia, it is the dominant treatment option.