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Find video protocols related to scientific articles indexed in Pubmed.
The Association Between Shortened Leukocyte Telomere Length and Cardio-Metabolic Outcomes: A Systematic Review and Meta-Analysis.
Circ Cardiovasc Genet
PUBLISHED: 11-20-2014
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-Telomeres are repetitive, gene-poor regions that cap the ends of DNA and help maintain chromosomal integrity. Their shortening is caused by inflammation and oxidative stress within the cellular environment and ultimately leads to cellular senescence. Shortened leukocyte telomere length (LTL) is hypothesized to be a novel biomarker for age and age-related diseases, yet reports on its association with cardio-metabolic outcomes in the literature are conflicting.
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Cerebrovascular reactivity predicts stroke in high-grade carotid artery disease.
Neurology
PUBLISHED: 09-12-2014
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To assess the usefulness of transcranial Doppler CO2 reactivity (CO2R) for prediction of ipsilateral ischemic stroke in carotid artery stenosis and occlusion with a meta-analysis of prospective studies based on individual patient data.
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Statins for acute coronary syndrome.
Cochrane Database Syst Rev
PUBLISHED: 09-01-2014
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The early period following the onset of acute coronary syndrome (ACS) represents a critical stage of coronary heart disease, with a high risk of recurrent events and deaths. The short-term effects of early treatment with statins on patient-relevant outcomes in patients suffering from ACS are unclear. This is an update of a review previously published in 2011.
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Corticosteroid treatment for community-acquired pneumonia--the STEP trial: study protocol for a randomized controlled trial.
Trials
PUBLISHED: 06-16-2014
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Community-acquired pneumonia (CAP) is the third-leading infectious cause of death worldwide. The standard treatment of CAP has not changed for the past fifty years and its mortality and morbidity remain high despite adequate antimicrobial treatment. Systemic corticosteroids have anti-inflammatory effects and are therefore discussed as adjunct treatment for CAP. Available studies show controversial results, and the question about benefits and harms of adjunct corticosteroid therapy has not been conclusively resolved, particularly in the non-critical care setting.
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Investigation of continuous effect modifiers in a meta-analysis on higher versus lower PEEP in patients requiring mechanical ventilation--protocol of the ICEM study.
Syst Rev
PUBLISHED: 01-28-2014
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Categorizing an inherently continuous predictor in prognostic analyses raises several critical methodological issues: dependence of the statistical significance on the number and position of the chosen cut-point(s), loss of statistical power, and faulty interpretation of the results if a non-linear association is incorrectly assumed to be linear. This also applies to a therapeutic context where investigators of randomized clinical trials (RCTs) are interested in interactions between treatment assignment and one or more continuous predictors.
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Methodological survey of designed uneven randomization trials (DU-RANDOM): a protocol.
Trials
PUBLISHED: 01-16-2014
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Although even randomization (that is, approximately 1:1 randomization ratio in study arms) provides the greatest statistical power, designed uneven randomization (DUR), (for example, 1:2 or 1:3) is used to increase participation rates. Until now, no convincing data exists addressing the impact of DUR on participation rates in trials. The objective of this study is to evaluate the epidemiology and to explore factors associated with DUR.
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A methodological survey of the analysis, reporting and interpretation of Absolute Risk ReductiOn in systematic revieWs (ARROW): a study protocol.
Syst Rev
PUBLISHED: 09-10-2013
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Clinicians, providers and guideline panels use absolute effects to weigh the advantages and downsides of treatment alternatives. Relative measures have the potential to mislead readers. However, little is known about the reporting of absolute measures in systematic reviews. The objectives of our study are to determine the proportion of systematic reviews that report absolute measures of effect for the most important outcomes, and ascertain how they are analyzed, reported and interpreted.
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Procalcitonin to initiate or discontinue antibiotics in acute respiratory tract infections.
Evid Based Child Health
PUBLISHED: 07-24-2013
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Acute respiratory infections (ARIs) comprise a large and heterogeneous group of infections including bacterial, viral and other aetiologies. In recent years, procalcitonin - the prohormone of calcitonin - has emerged as a promising marker for the diagnosis of bacterial infections and for improving decisions about antibiotic therapy. Several randomised controlled trials (RCTs) have demonstrated the feasibility of using procalcitonin for starting and stopping antibiotics in different patient populations with acute respiratory infections and different settings ranging from primary care to emergency departments (EDs), hospital wards and intensive care units (ICUs).
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Initiation and continuation of randomized trials after the publication of a trial stopped early for benefit asking the same study question: STOPIT-3 study design.
Trials
PUBLISHED: 06-03-2013
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Randomized control trials (RCTs) stopped early for benefit (truncated RCTs) are increasingly common and, on average, overestimate the relative magnitude of benefit by approximately 30%. Investigators stop trials early when they consider it is no longer ethical to enroll patients in a control group. The goal of this systematic review is to determine how investigators of ongoing or planned RCTs respond to the publication of a truncated RCT addressing a similar question.Methods/designWe will conduct systematic reviews to update the searches of 210 truncated RCTs to identify similar trials ongoing at the time of publication, or started subsequently, to the truncated trials (subsequent RCTs). Reviewers will determine in duplicate the similarity between the truncated and subsequent trials. We will analyze the epidemiology, distribution, and predictors of subsequent RCTs. We will also contact authors of subsequent trials to determine reasons for beginning, continuing, or prematurely discontinuing their own trials, and the extent to which they rely on the estimates from truncated trials.
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Short-term vs conventional glucocorticoid therapy in acute exacerbations of chronic obstructive pulmonary disease: the REDUCE randomized clinical trial.
JAMA
PUBLISHED: 05-23-2013
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International guidelines advocate a 7- to 14-day course of systemic glucocorticoid therapy in acute exacerbations of chronic obstructive pulmonary disease (COPD). However, the optimal dose and duration are unknown.
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How to write a surgical clinical research protocol: literature review and practical guide.
Am. J. Surg.
PUBLISHED: 04-24-2013
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The study protocol is the core document of every clinical research project. Clinical research in studies involving surgical interventions presents some specific challenges, which need to be accounted for and described in the study protocol. The aim of this review is to provide a practical guide for developing a clinical study protocol for surgical interventions with a focus on methodologic issues.
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Detecting, quantifying and adjusting for publication bias in meta-analyses: protocol of a systematic review on methods.
Syst Rev
PUBLISHED: 04-09-2013
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Health professionals and policymakers aspire to make healthcare decisions based on the entire relevant research evidence. This, however, can rarely be achieved because a considerable amount of research findings are not published, especially in case of negative results - a phenomenon widely recognized as publication bias. Different methods of detecting, quantifying and adjusting for publication bias in meta-analyses have been described in the literature, such as graphical approaches and formal statistical tests to detect publication bias, and statistical approaches to modify effect sizes to adjust a pooled estimate when the presence of publication bias is suspected. An up-to-date systematic review of the existing methods is lacking.
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Defining publication bias: protocol for a systematic review of highly cited articles and proposal for a new framework.
Syst Rev
PUBLISHED: 04-09-2013
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Selective publication of studies, which is commonly called publication bias, is widely recognized. Over the years a new nomenclature for other types of bias related to non-publication or distortion related to the dissemination of research findings has been developed. However, several of these different biases are often still summarized by the term publication bias.
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A users guide to understanding therapeutic substitutions.
J Clin Epidemiol
PUBLISHED: 03-16-2013
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Therapeutic substitutions are common at the level of ministries of health, clinicians, and pharmacy dispensaries. Guidance in determining whether drugs offer similar risk-benefit profiles is limited. Those making decisions on therapeutic substitutions should be aware of potential biases that make differentiating therapeutic agents difficult. Readers should consider whether the biological mechanisms and doses are similar across agents, whether the evidence is sufficiently valid across agents, and whether the safety and therapeutic effects of each drug are similar. This article uses a problem-based format to address the biological mechanism, validity, and results of a scenario in which therapeutic substitutions may be considered.
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A systematic review of nonabsorbable, absorbable, and steroid-impregnated spacers following endoscopic sinus surgery.
Int Forum Allergy Rhinol
PUBLISHED: 03-10-2013
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Middle meatal (MM) spacers may reduce adhesions following endoscopic sinus surgery (ESS). However, there is no consensus as to which materials and adjuncts are the most effective for this purpose. The primary objective of this study was to examine the effectiveness of absorbable spacers (AS) vs nonabsorbable spacers (NAS) in reducing adhesions following ESS for chronic sinusitis. Secondarily, we assessed steroidal vs nonsteroidal MM spacers in reducing adhesions.
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Clinical outcomes associated with procalcitonin algorithms to guide antibiotic therapy in respiratory tract infections.
JAMA
PUBLISHED: 02-21-2013
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In patients with respiratory tract infection, is measurement of procalcitonin to guide antibiotic prescriptions associated with reduced antibiotic exposure without increases in all-cause mortality or treatment failure?
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A protocol for a systematic review on the impact of unpublished studies and studies published in the gray literature in meta-analyses.
Syst Rev
PUBLISHED: 01-23-2013
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Meta-analyses are particularly vulnerable to the effects of publication bias. Despite methodologists best efforts to locate all evidence for a given topic the most comprehensive searches are likely to miss unpublished studies and studies that are published in the gray literature only. If the results of the missing studies differ systematically from the published ones, a meta-analysis will be biased with an inaccurate assessment of the interventions effects.As part of the OPEN project (http://www.open-project.eu) we will conduct a systematic review with the following objectives:? To assess the impact of studies that are not published or published in the gray literature on pooled effect estimates in meta-analyses (quantitative measure).? To assess whether the inclusion of unpublished studies or studies published in the gray literature leads to different conclusions in meta-analyses (qualitative measure).
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Publication bias in animal research: a systematic review protocol.
Syst Rev
PUBLISHED: 01-23-2013
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Systematic reviews and meta-analyses of pre-clinical studies, in vivo animal experiments in particular, can influence clinical care. Publication bias is one of the major threats of validity in systematic reviews and meta-analyses. Previous empirical studies suggested that systematic reviews and meta-analyses have become more prevalent until 2010 and found evidence for compromised methodological rigor with a trend towards improvement. We aim to comprehensively summarize and update the evidence base on systematic reviews and meta-analyses of animal studies, their methodological quality and assessment of publication bias in particular.
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Addressing dichotomous data for participants excluded from trial analysis: a guide for systematic reviewers.
PLoS ONE
PUBLISHED: 01-17-2013
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Systematic reviewer authors intending to include all randomized participants in their meta-analyses need to make assumptions about the outcomes of participants with missing data.
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Substitutes of structural and non-structural autologous bone grafts in hindfoot arthrodeses and osteotomies: a systematic review.
BMC Musculoskelet Disord
PUBLISHED: 01-16-2013
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Structural and non-structural substitutes of autologous bone grafts are frequently used in hindfoot arthrodeses and osteotomies. However, their efficacy is unclear.The primary goal of this systematic review was to compare autologous bone grafts with structural and non-structural substitutes regarding the odds of union in hindfoot arthrodeses and osteotomies.
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Somatostatin-based radiotherapy with [90Y-DOTA]-TOC in neuroendocrine tumors: long-term outcome of a phase I dose escalation study.
J Transl Med
PUBLISHED: 01-09-2013
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We describe the long-term outcome after clinical introduction and dose escalation of somatostatin receptor targeted therapy with [90Y-DOTA]-TOC in patients with metastasized neuroendocrine tumors.
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Reflections on meta-analyses involving trials stopped early for benefit: is there a problem and if so, what is it?
Stat Methods Med Res
PUBLISHED: 12-13-2011
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We review controversies associated with randomized controlled trials (RCTs) stopped early for apparent benefit (truncated RCTs or tRCTs) and present our groups perspective. Long-established theory, simulations and recent empirical evidence demonstrate that tRCTs will on average overestimate treatment effects, and this overestimation may be large, particularly when tRCTs have small number of events. Theoretical considerations and simulations demonstrate that on average, meta-analyses of RCTs with appropriate stopping rules will lead to only trivial overestimation of treatment effects. However, tRCTs will disproportionally contribute to meta-analytic estimates when tRCTs occur early in the sequence of trials with few subsequent studies, publication of nontruncated RCTs is delayed, there is publication bias, or tRCTs result in a freezing effect in which correcting trials are never undertaken. To avoid applying overestimates of effect to clinical decision-making, clinicians should view the results of individual tRCTs with small sample sizes and small number of events with skepticism. Pooled effects from meta-analyses including tRCTs are likely to overestimate effect when there is a substantial difference in effect estimates between the tRCTs and the nontruncated RCTs, and in which the tRCTs have a substantial weight in the meta-analysis despite themselves having a relatively small number of events. Such circumstances call for sensitivity analyses omitting tRCTs.
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The impact of 18F-FDG PET on the management of patients with suspected large vessel vasculitis.
Eur. J. Nucl. Med. Mol. Imaging
PUBLISHED: 08-15-2011
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We aimed to assess the impact of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on the management of patients with suspected large vessel vasculitis.
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Procalcitonin algorithms for antibiotic therapy decisions: a systematic review of randomized controlled trials and recommendations for clinical algorithms.
Arch. Intern. Med.
PUBLISHED: 08-10-2011
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Previous randomized controlled trials suggest that using clinical algorithms based on procalcitonin levels, a marker of bacterial infections, results in reduced antibiotic use without a deleterious effect on clinical outcomes. However, algorithms differed among trials and were embedded primarily within the European health care setting. Herein, we summarize the design, efficacy, and safety of previous randomized controlled trials and propose adapted algorithms for US settings. We performed a systematic search and included all 14 randomized controlled trials (N = 4467 patients) that investigated procalcitonin algorithms for antibiotic treatment decisions in adult patients with respiratory tract infections and sepsis from primary care, emergency department (ED), and intensive care unit settings. We found no significant difference in mortality between procalcitonin-treated and control patients overall (odds ratio, 0.91; 95% confidence interval, 0.73-1.14) or in primary care (0.13; 0-6.64), ED (0.95; 0.67-1.36), and intensive care unit (0.89; 0.66-1.20) settings individually. A consistent reduction was observed in antibiotic prescription and/or duration of therapy, mainly owing to lower prescribing rates in low-acuity primary care and ED patients, and shorter duration of therapy in moderate- and high-acuity ED and intensive care unit patients. Measurement of procalcitonin levels for antibiotic decisions in patients with respiratory tract infections and sepsis appears to reduce antibiotic exposure without worsening the mortality rate. We propose specific procalcitonin algorithms for low-, moderate-, and high-acuity patients as a basis for future trials aiming at reducing antibiotic overconsumption.
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Statins for acute coronary syndrome.
Cochrane Database Syst Rev
PUBLISHED: 06-17-2011
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The early period following the onset of acute coronary syndromes (ACS) represents a critical stage of coronary heart disease with a high risk for recurrent events and deaths. The short-term effects of early treatment with statins in patients suffering from ACS on patient-relevant outcomes are unclear.
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Economic evaluation of reamed versus unreamed intramedullary nailing in patients with closed and open tibial fractures: results from the study to prospectively evaluate reamed intramedullary nails in patients with tibial fractures (SPRINT).
Value Health
PUBLISHED: 05-25-2011
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Recently, results from the large, randomized study to prospectively evaluate reamed intramedullary nails in patients with tibial fractures (SPRINT) trial suggested a benefit for reamed intramedullary nail insertion in patients with closed tibial shaft fractures largely based on cost-neutral autodynamizations and a potential advantage for unreamed intramedullary nailing in open fractures. We performed an economic evaluation to compare resource use and effectiveness of reamed and unreamed intramedullary nailing using a cost-utility analysis.
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Response, survival, and long-term toxicity after therapy with the radiolabeled somatostatin analogue [90Y-DOTA]-TOC in metastasized neuroendocrine cancers.
J. Clin. Oncol.
PUBLISHED: 05-09-2011
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To investigate response, survival, and safety profile of the somatostatin-based radiopeptide (90)yttrium-labeled tetraazacyclododecane-tetraacetic acid modified Tyr-octreotide ([(90)Y-DOTA]-TOC) in neuroendocrine cancers.
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Randomisation to protect against selection bias in healthcare trials.
Cochrane Database Syst Rev
PUBLISHED: 04-15-2011
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Randomised trials use the play of chance to assign participants to comparison groups. The unpredictability of the process, if not subverted, should prevent systematic differences between comparison groups (selection bias). Differences due to chance will still occur and these are minimised by randomising a sufficiently large number of people.
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Meta-analysis comparing Mediterranean to low-fat diets for modification of cardiovascular risk factors.
Am. J. Med.
PUBLISHED: 03-09-2011
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Evidence from individual trials comparing Mediterranean to low-fat diets to modify cardiovascular risk factors remains preliminary.
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Intensive statin therapy compared with moderate dosing for prevention of cardiovascular events: a meta-analysis of >40 000 patients.
Eur. Heart J.
PUBLISHED: 03-08-2011
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Statin therapy is associated with important benefits for patients at risk of, and with, established cardiovascular disease. There is widespread interest in whether intensive dosing of statins yields larger treatment effects. We aimed to determine if intensive dosing is clinically important using a meta-analysis of randomized clinical trials (RCTs).
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Specific instructions for estimating unclearly reported blinding status in randomized trials were reliable and valid.
J Clin Epidemiol
PUBLISHED: 03-01-2011
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To test the reliability and validity of specific instructions to classify blinding, when unclearly reported in randomized trials, as "probably done" or "probably not done."
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Vasopressor administration and sepsis: a survey of Canadian intensivists.
J Crit Care
PUBLISHED: 01-13-2011
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Patients with septic shock often receive intravenous vasopressor infusions, with little evidence available to guide their titration. We surveyed Canadian intensivists to document self-reported vasopressor titration strategies for patients with septic shock.
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Updated evidence on early statin therapy for acute coronary syndromes: meta-analysis of 18 randomized trials involving over 14,000 patients.
Int. J. Cardiol.
PUBLISHED: 01-09-2011
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The short-term effects of early statin therapy in acute coronary syndromes (ACS) on clinical outcomes remain unclear. Our objective was to update the evidence on patient relevant outcomes from all randomized trials comparing early statin therapy with placebo or usual care at 1 and 4 months following ACS.
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Short versus conventional term glucocorticoid therapy in acute exacerbation of chronic obstructive pulmonary disease - the "REDUCE" trial.
Swiss Med Wkly
PUBLISHED: 12-08-2010
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International guidelines advocate a 10 to 14-day course of systemic glucocorticoid therapy in the management of COPD exacerbations. The optimal duration of therapy is unknown and glucocorticoids have serious adverse effects. The aim of this trial is to demonstrate non-inferiority of a five-day compared to a 14-day course of systemic glucocorticoids with respect to COPD outcome, thereby significantly reducing steroid exposure and side effects in patients with COPD exacerbations.
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Systematic review of reviews including animal studies addressing therapeutic interventions for sepsis.
Crit. Care Med.
PUBLISHED: 10-05-2010
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Certain methodologic features of animal experiments such as random assignment have been found to reduce the risk of bias. Because animal research sometimes informs clinical practice, explicit acknowledgment of the risk of bias and clinical relevance cultivates realistic expectations on the part of clinicians reading preclinical studies. We assessed literature reviews of therapeutic interventions for sepsis that include animal experiments for explicit appraisals of the risk of bias and clinical relevance.
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Higher vs lower positive end-expiratory pressure in patients with acute lung injury and acute respiratory distress syndrome: systematic review and meta-analysis.
JAMA
PUBLISHED: 03-04-2010
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Trials comparing higher vs lower levels of positive end-expiratory pressure (PEEP) in adults with acute lung injury or acute respiratory distress syndrome (ARDS) have been underpowered to detect small but potentially important effects on mortality or to explore subgroup differences.
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Subgroup Analysis of Trials Is Rarely Easy (SATIRE): a study protocol for a systematic review to characterize the analysis, reporting, and claim of subgroup effects in randomized trials.
Trials
PUBLISHED: 09-12-2009
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Subgroup analyses in randomized trials examine whether effects of interventions differ between subgroups of study populations according to characteristics of patients or interventions. However, findings from subgroup analyses may be misleading, potentially resulting in suboptimal clinical and health decision making. Few studies have investigated the reporting and conduct of subgroup analyses and a number of important questions remain unanswered. The objectives of this study are: 1) to describe the reporting of subgroup analyses and claims of subgroup effects in randomized controlled trials, 2) to assess study characteristics associated with reporting of subgroup analyses and with claims of subgroup effects, and 3) to examine the analysis, and interpretation of subgroup effects for each studys primary outcome.
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Cost-effectiveness of drug-eluting stents in a US Medicare setting:a cost-utility analysis with 3-year clinical follow-up data.
Value Health
PUBLISHED: 06-04-2009
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There is only limited information about cost-effectiveness of drug-eluting compared with bare metal stents (BMS) over a time horizon of more than 1 year.
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Choice of data extraction tools for systematic reviews depends on resources and review complexity.
J Clin Epidemiol
PUBLISHED: 04-08-2009
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To assist investigators planning, coordinating, and conducting systematic reviews in the selection of data-extraction tools for conducting systematic reviews.
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Corticosteroid therapy for acute lung injury, acute respiratory distress syndrome, and severe pneumonia: a meta-analysis of randomized controlled trials.
J Crit Care
PUBLISHED: 03-26-2009
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Randomized trials investigating the effect of corticosteroids in the treatment of acute lung injury, acute respiratory distress syndrome, and severe pneumonia have had mixed results. We sought to determine whether systemic corticosteroids reduce hospital mortality from these illnesses.
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LOST to follow-up Information in Trials (LOST-IT): a protocol on the potential impact.
Trials
PUBLISHED: 03-03-2009
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Incomplete ascertainment of outcomes in randomized controlled trials (RCTs) is likely to bias final study results if reasons for unavailability of patient data are associated with the outcome of interest. The primary objective of this study is to assess the potential impact of loss to follow-up on the estimates of treatment effect. The secondary objectives are to describe, for published RCTs, (1) the reporting of loss to follow-up information, (2) the analytic methods used for handling loss to follow-up information, and (3) the extent of reported loss to follow-up.
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Association between change in high density lipoprotein cholesterol and cardiovascular disease morbidity and mortality: systematic review and meta-regression analysis.
BMJ
PUBLISHED: 02-18-2009
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To investigate the association between treatment induced change in high density lipoprotein cholesterol and total death, coronary heart disease death, and coronary heart disease events (coronary heart disease death and non-fatal myocardial infarction) adjusted for changes in low density lipoprotein cholesterol and drug class in randomised trials of lipid modifying interventions.
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Stopping randomized trials early for benefit: a protocol of the Study Of Trial Policy Of Interim Truncation-2 (STOPIT-2).
Trials
PUBLISHED: 02-11-2009
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Randomized clinical trials (RCTs) stopped early for benefit often receive great attention and affect clinical practice, but pose interpretational challenges for clinicians, researchers, and policy makers. Because the decision to stop the trial may arise from catching the treatment effect at a random high, truncated RCTs (tRCTs) may overestimate the true treatment effect. The Study Of Trial Policy Of Interim Truncation (STOPIT-1), which systematically reviewed the epidemiology and reporting quality of tRCTs, found that such trials are becoming more common, but that reporting of stopping rules and decisions were often deficient. Most importantly, treatment effects were often implausibly large and inversely related to the number of the events accrued. The aim of STOPIT-2 is to determine the magnitude and determinants of possible bias introduced by stopping RCTs early for benefit.
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Inconsistent definitions for intention-to-treat in relation to missing outcome data: systematic review of the methods literature.
PLoS ONE
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Authors of randomized trial reports seem to hold a variety of views regarding the relationship between missing outcome data (MOD) and intention to treat (ITT). The objectives of this study were to systematically investigate how authors of methodology articles define ITT in the presence of MOD, how they recommend handling MOD under ITT, and to make a proposal for potential improvement in the definition and use of ITT in relation to MOD.
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Procalcitonin to initiate or discontinue antibiotics in acute respiratory tract infections.
Cochrane Database Syst Rev
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Acute respiratory infections (ARIs) comprise a large and heterogeneous group of infections including bacterial, viral and other aetiologies. In recent years, procalcitonin - the prohormone of calcitonin - has emerged as a promising marker for the diagnosis of bacterial infections and for improving decisions about antibiotic therapy. Several randomised controlled trials (RCTs) have demonstrated the feasibility of using procalcitonin for starting and stopping antibiotics in different patient populations with acute respiratory infections and different settings ranging from primary care to emergency departments (EDs), hospital wards and intensive care units (ICUs).
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Learning from failure--rationale and design for a study about discontinuation of randomized trials (DISCO study).
BMC Med Res Methodol
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Randomized controlled trials (RCTs) may be discontinued because of apparent harm, benefit, or futility. Other RCTs are discontinued early because of insufficient recruitment. Trial discontinuation has ethical implications, because participants consent on the premise of contributing to new medical knowledge, Research Ethics Committees (RECs) spend considerable effort reviewing study protocols, and limited resources for conducting research are wasted. Currently, little is known regarding the frequency and characteristics of discontinued RCTs.
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The dangers of stopping a trial too early.
J Bone Joint Surg Am
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To ensure that participants in randomized controlled trials are protected from harm, interim analyses and review of results by an independent data monitoring committee have become standard practice. If an analysis of accumulating data partway through a trial reveals an unanticipated degree of benefit or toxicity, or differences in outcomes between the intervention and control groups are so unimpressive that any prospect of a positive result with the planned sample size is extremely unlikely, investigators may stop the trial earlier than originally scheduled. The practice of stopping randomized controlled trials early is, however, problematic, especially if the trial is stopped for apparent benefit. Concerns in trials stopped early for apparent benefit include appropriate interpretation of results and ethical problems concerning trial participants, clinicians, and society as a whole. In this article, we review the epidemiology of trials stopped early and illustrate some of the problems and controversies associated with stopping randomized controlled trials early for apparent benefit. Finally, we offer guidance for clinicians, those running clinical trials, and authors of systematic reviews.
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Procalcitonin to guide initiation and duration of antibiotic treatment in acute respiratory infections: an individual patient data meta-analysis.
Clin. Infect. Dis.
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Procalcitonin algorithms may reduce antibiotic use for acute respiratory tract infections (ARIs). We undertook an individual patient data meta-analysis to assess safety of this approach in different ARI diagnoses and different clinical settings.
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Blockade of the renin-angiotensin-aldosterone system (RAAS) for primary prevention of non-valvular atrial fibrillation: a systematic review and meta analysis of randomized controlled trials.
Int. J. Cardiol.
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The renin-angiotensin-aldosterone system is suggested to play a key role in the development of atrial fibrillation through structural and electrical remodeling. This review aims to assess the effectiveness of blockade of the renin-angiotensin-aldosterone system in the prevention of new onset atrial fibrillation.
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Meta-analyses: what they can and cannot do.
Swiss Med Wkly
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Meta-analyses overcome the limitation of small sample sizes or rare outcomes by pooling results from a number of individual studies to generate a single best estimate. As long as a meta-analysis is not limited by poor quality of included trials, unexplainable heterogeneity and/or reporting bias of individual trials, meta-analyses can be instrumental in reliably demonstrating benefit or harm of an intervention when results of individual randomised controlled trials are conflicting or inconclusive. Therefore meta-analyses should be conducted as part of a systematic review, i.e., a systematic approach to answer a focused clinical question. Important features of a systematic review are a comprehensive, reproducible search for primary studies, selection of studies using clear and transparent eligibility criteria, standardised critical appraisal of studies for quality, and investigation of heterogeneity among included studies. Cumulative meta-analysis may prevent delays in the introduction of effective treatments and may allow for early detection of harmful effects of interventions. As opposed to meta-analysis based on aggregate study data, individual patient data meta-analyses offer the advantage to use standardised criteria across trials and reliably investigate subgroup effects of interventions. Network meta-analysis allows the integration of data from direct and indirect comparisons in order to compare multiple treatments in a comprehensive analysis and determine the best treatment among several options. We conclude that meta-analysis has become a popular, versatile, and powerful tool. If rigorously conducted as part of a systematic review, it is essential for evidence-based decision making in clinical practice as well as on the health policy level.
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Cohort study of somatostatin-based radiopeptide therapy with [(90)Y-DOTA]-TOC versus [(90)Y-DOTA]-TOC plus [(177)Lu-DOTA]-TOC in neuroendocrine cancers.
J. Clin. Oncol.
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Radiopeptide therapy is commonly performed with a single radioisotope. We aimed to compare the effectiveness of somatostatin-based radiopeptide therapy with a single versus a combination of radioisotopes.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.