109 results on '"Altman, Douglas G"'
Search Results
2. CONSORT Statement on the Reporting Standards of Clinical Trials
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Meade, T. W., Wald, Nicholas, Collins, Rory, Bromhead, Helen J., Goodman, Neville W., O'Toole, Liam B., Altman, Douglas G., Moher, David, and Rennie, Drummond
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- 1997
3. Development process of a consensus-driven CONSORT extension for randomised trials using an adaptive design.
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Dimairo, Munyaradzi, Coates, Elizabeth, Julious, Steven A., Biggs, Katie, Nicholl, Jon, Hind, Daniel, Hamasaki, Toshimitsu, Proschan, Michael A., Scott, John A., Ando, Yuki, Altman, Douglas G., Pallmann, Philip, Todd, Susan, Jaki, Thomas, Mander, Adrian P., Wason, James, Weir, Christopher J., Koenig, Franz, and Walton, Marc K.
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CLINICAL trials ,RANDOMIZED controlled trials ,DECISION making ,RESEARCH ethics ,LITERATURE reviews ,CLINICAL trial registries - Abstract
Background: Adequate reporting of adaptive designs (ADs) maximises their potential benefits in the conduct of clinical trials. Transparent reporting can help address some obstacles and concerns relating to the use of ADs. Currently, there are deficiencies in the reporting of AD trials. To overcome this, we have developed a consensus-driven extension to the CONSORT statement for randomised trials using an AD. This paper describes the processes and methods used to develop this extension rather than detailed explanation of the guideline.Methods: We developed the guideline in seven overlapping stages: 1) Building on prior research to inform the need for a guideline; 2) A scoping literature review to inform future stages; 3) Drafting the first checklist version involving an External Expert Panel; 4) A two-round Delphi process involving international, multidisciplinary, and cross-sector key stakeholders; 5) A consensus meeting to advise which reporting items to retain through voting, and to discuss the structure of what to include in the supporting explanation and elaboration (E&E) document; 6) Refining and finalising the checklist; and 7) Writing-up and dissemination of the E&E document. The CONSORT Executive Group oversaw the entire development process.Results: Delphi survey response rates were 94/143 (66%), 114/156 (73%), and 79/143 (55%) in rounds 1, 2, and across both rounds, respectively. Twenty-seven delegates from Europe, the USA, and Asia attended the consensus meeting. The main checklist has seven new and nine modified items and six unchanged items with expanded E&E text to clarify further considerations for ADs. The abstract checklist has one new and one modified item together with an unchanged item with expanded E&E text. The E&E document will describe the scope of the guideline, the definition of an AD, and some types of ADs and trial adaptations and explain each reporting item in detail including case studies.Conclusions: We hope that making the development processes, methods, and all supporting information that aided decision-making transparent will enhance the acceptability and quick uptake of the guideline. This will also help other groups when developing similar CONSORT extensions. The guideline is applicable to all randomised trials with an AD and contains minimum reporting requirements. [ABSTRACT FROM AUTHOR]- Published
- 2018
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4. Associations Between Adding a Radial Artery Graft to Single and Bilateral Internal Thoracic Artery Grafts and Outcomes: Insights From the Arterial Revascularization Trial.
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Taggart, David P., Altman, Douglas G., Flather, Marcus, Gerry, Stephen, Gray, Alastair, Lees, Belinda, Benedetto, Umberto, and ART (Arterial Revascularization Trial) Investigators
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RADIAL artery , *INTERNAL thoracic artery , *REVASCULARIZATION (Surgery) , *HEALTH outcome assessment , *SAPHENOUS vein , *ADVERSE health care events , *SURGERY , *CALCIUM antagonists , *DIAGNOSIS , *PERIPHERAL vascular disease treatment , *COMPARATIVE studies , *CORONARY artery bypass , *CORONARY disease , *RESEARCH methodology , *MEDICAL cooperation , *MYOCARDIAL infarction , *PROBABILITY theory , *REOPERATION , *RESEARCH , *RESEARCH funding , *SURVIVAL , *DISEASE relapse , *EVALUATION research , *RANDOMIZED controlled trials , *TREATMENT effectiveness , *PROPORTIONAL hazards models , *TRANSPLANTATION of organs, tissues, etc. , *THERAPEUTICS ,MYOCARDIAL infarction diagnosis ,MYOCARDIAL infarction-related mortality ,THORACIC artery transplantation - Abstract
Background: Whether the use of the radial artery (RA) can improve clinical outcomes in coronary artery bypass graft surgery remains unclear. The ART (Arterial Revascularization Trial) was designed to compare survival after bilateral internal thoracic artery (BITA) over single left internal thoracic artery (SITA). In the ART, a large proportion of patients (≈20%) also received an RA graft instead of a saphenous vein graft (SVG). We aimed to investigate the associations between using the RA instead of an SVG to supplement SITA or BITA grafts and outcomes by performing a post hoc analysis of the ART.Methods: Patients enrolled in the ART (n=3102) were classified on the basis of conduits actually received (as treated). The analysis included 2737 patients who received an RA graft (RA group; n=632) or SVG only (SVG group; n=2105) in addition to SITA or BITA grafts. The primary end point was the composite of myocardial infarction, cardiovascular death, and repeat revascularization at 5 years. Propensity score matching and stratified Cox regression were used to compare the 2 strategies.Results: Myocardial infarction, cardiovascular death, and repeat revascularization cumulative incidence was 2.3% (95% confidence interval [CI], 1.1-3.4), 3.5% (95% CI, 2.1-5.0), and 4.4% (95% CI, 2.8-6.0) in the RA group and 3.4% (95% CI, 2.0-4.8), 4.0% (95% CI, 2.5-5.6), and 7.6% (95% CI, 5.5-9.7) in the SVG group, respectively. The composite end point was significantly lower in the RA group (8.8%; 95% CI, 6.5-11.0) compared with the SVG group (13.6%; 95% CI, 10.8-16.3; P=0.005). This association was present when an RA graft was used to supplement both SITA and BITA grafts (interaction P=0.62).Conclusions: This post hoc ART analysis showed that an additional RA was associated with lower risk for midterm major adverse cardiac events when used to supplement SITA or BITA grafts.Clinical Trial Registration: URL: https://www.situ.ox.ac.uk/surgical-trials/art. Unique identifier: ISRCTN46552265. [ABSTRACT FROM AUTHOR]- Published
- 2017
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5. CONSORT Statement for Randomized Trials of Nonpharmacologic Treatments: A 2017 Update and a CONSORT Extension for Nonpharmacologic Trial Abstracts.
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Boutron, Isabelle, Altman, Douglas G., Moher, David, Schulz, Kenneth F., and Ravaud, Philippe
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CLINICAL trials , *RANDOMIZED controlled trials , *CLINICAL trial registries , *MEDICAL research , *RESEARCH bias - Abstract
Incomplete and inadequate reporting is an avoidable waste that reduces the usefulness of research. The CONSORT (Consolidated Standards of Reporting Trials) Statement is an evidence-based reporting guideline that aims to improve research transparency and reduce waste. In 2008, the CONSORT Group developed an extension to the original statement that addressed methodological issues specific to trials of nonpharmacologic treatments (NPTs), such as surgery, rehabilitation, or psychotherapy. This article describes an update of that extension and presents an extension for reporting abstracts of NPT trials. To develop these materials, the authors reviewed pertinent literature published up to July 2016; surveyed authors of NPT trials; and conducted a consensus meeting with editors, trialists, and methodologists. Changes to the CONSORT Statement extension for NPT trials include wording modifications to improve readers' understanding and the addition of 3 new items. These items address whether and how adherence of participants to interventions is assessed or enhanced, description of attempts to limit bias if blinding is not possible, and specification of the delay between randomization and initiation of the intervention. The CONSORT extension for abstracts of NPT trials includes 2 new items that were not specified in the original CONSORT Statement for abstracts. The first addresses reporting of eligibility criteria for centers where the intervention is performed and for care providers. The second addresses reporting of important changes to the intervention versus what was planned. Both the updated CONSORT extension for NPT trials and the CONSORT extension for NPT trial abstracts should help authors, editors, and peer reviewers improve the transparency of NPT trial reports. [ABSTRACT FROM AUTHOR]
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- 2017
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6. Randomized Trial of Bilateral versus Single Internal-Thoracic-Artery Grafts.
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Taggart, David P., Altman, Douglas G., Gray, Alastair M., Lees, Belinda, Gerry, Stephen, Benedetto, Umberto, Flather, Marcus, and ART Investigators
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INTERNAL thoracic artery , *CORONARY artery bypass , *TRANSPLANTATION of organs, tissues, etc. , *TREATMENT effectiveness , *RANDOMIZED controlled trials , *CORONARY heart disease surgery , *COMPARATIVE studies , *CORONARY disease , *CAUSES of death , *LONGITUDINAL method , *RESEARCH methodology , *MEDICAL cooperation , *MYOCARDIAL infarction , *RESEARCH , *RESEARCH funding , *STROKE , *SURVIVAL , *EVALUATION research , *DISEASE incidence - Abstract
Background: The use of bilateral internal thoracic (mammary) arteries for coronary-artery bypass grafting (CABG) may improve long-term outcomes as compared with the use of a single internal-thoracic-artery plus vein grafts.Methods: We randomly assigned patients scheduled for CABG to undergo single or bilateral internal-thoracic-artery grafting in 28 cardiac surgical centers in seven countries. The primary outcome was death from any cause at 10 years. The composite of death from any cause, myocardial infarction, or stroke was a secondary outcome. Interim analyses were prespecified at 5 years of follow-up.Results: A total of 3102 patients were enrolled; 1554 were randomly assigned to undergo single internal-thoracic-artery grafting (the single-graft group) and 1548 to undergo bilateral internal-thoracic-artery grafting (the bilateral-graft group). At 5 years of follow-up, the rate of death was 8.7% in the bilateral-graft group and 8.4% in the single-graft group (hazard ratio, 1.04; 95% confidence interval [CI], 0.81 to 1.32; P=0.77), and the rate of the composite of death from any cause, myocardial infarction, or stroke was 12.2% and 12.7%, respectively (hazard ratio, 0.96; 95% CI, 0.79 to 1.17; P=0.69). The rate of sternal wound complication was 3.5% in the bilateral-graft group versus 1.9% in the single-graft group (P=0.005), and the rate of sternal reconstruction was 1.9% versus 0.6% (P=0.002).Conclusions: Among patients undergoing CABG, there was no significant difference between those receiving single internal-thoracic-artery grafts and those receiving bilateral internal-thoracic-artery grafts with regard to mortality or the rates of cardiovascular events at 5 years of follow-up. There were more sternal wound complications with bilateral internal-thoracic-artery grafting than with single internal-thoracic-artery grafting. Ten-year follow-up is ongoing. (Funded by the British Heart Foundation and others; ART Current Controlled Trials number, ISRCTN46552265 .). [ABSTRACT FROM AUTHOR]- Published
- 2016
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7. Impact of a web-based tool (WebCONSORT) to improve the reporting of randomised trials: results of a randomised controlled trial.
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Hopewell, Sally, Boutron, Isabelle, Altman, Douglas G., Barbour, Ginny, Moher, David, Montori, Victor, Schriger, David, Cook, Jonathan, Gerry, Stephen, Omar, Omar, Dutton, Peter, Roberts, Corran, Frangou, Eleni, Clifton, Lei, Chiocchia, Virginia, Rombach, Ines, Wartolowska, Karolina, and Ravaud, Philippe
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RANDOMIZED controlled trials ,MEDICAL periodicals ,MEDICAL publishing ,MANUSCRIPTS ,CLINICAL trials - Abstract
Background: The CONSORT Statement is an evidence-informed guideline for reporting randomised controlled trials. A number of extensions have been developed that specify additional information to report for more complex trials. The aim of this study was to evaluate the impact of using a simple web-based tool (WebCONSORT, which incorporates a number of different CONSORT extensions) on the completeness of reporting of randomised trials published in biomedical publications. Methods: We conducted a parallel group randomised trial. Journals which endorsed the CONSORT Statement (i.e. referred to it in the Instruction to Authors) but do not actively implement it (i.e. require authors to submit a completed CONSORT checklist) were invited to participate. Authors of randomised trials were requested by the editor to use the web-based tool at the manuscript revision stage. Authors registering to use the tool were randomised (centralised computer generated) to WebCONSORT or control. In the WebCONSORT group, they had access to a tool allowing them to combine the different CONSORT extensions relevant to their trial and generate a customised checklist and flow diagram that they must submit to the editor. In the control group, authors had only access to a CONSORT flow diagram generator. Authors, journal editors, and outcome assessors were blinded to the allocation. The primary outcome was the proportion of CONSORT items (main and extensions) reported in each article post revision. Results: A total of 46 journals actively recruited authors into the trial (25 March 2013 to 22 September 2015); 324 author manuscripts were randomised (WebCONSORT n = 166; control n = 158), of which 197 were reports of randomised trials (n=94; n = 103). Over a third (39%; n = 127) of registered manuscripts were excluded from the analysis, mainly because the reported study was not a randomised trial. Of those included in the analysis, the most common CONSORT extensions selected were non-pharmacologic (n = 43; n = 50), pragmatic (n = 20; n = 16) and cluster (n=10; n=9). In a quarter of manuscripts, authors either wrongly selected an extension or failed to select the right extension when registering their manuscript on the WebCONSORT study site. Overall, there was no important difference in the overall mean score between WebCONSORT (mean score 0.51) and control (0.47) in the proportion of CONSORT and CONSORT extension items reported pertaining to a given study (mean difference, 0.04; 95% CI -0.02 to 0.10). Conclusions: This study failed to show a beneficial effect of a customised web-based CONSORT checklist to help authors prepare more complete trial reports. However, the exclusion of a large number of inappropriately registered manuscripts meant we had less precision than anticipated to detect a difference. Better education is needed, earlier in the publication process, for both authors and journal editorial staff on when and how to implement CONSORT and, in particular, CONSORT-related extensions. [ABSTRACT FROM AUTHOR]
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- 2016
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8. Update on the endorsement of CONSORT by high impact factor journals: a survey of journal "Instructions to Authors" in 2014.
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Shamseer, Larissa, Hopewell, Sally, Altman, Douglas G., Moher, David, and Schulz, Kenneth F.
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CROSS-sectional method ,MEDICAL research ,RANDOMIZED controlled trials ,PUBLISHING ,AUTHORSHIP ,CLINICAL trials ,NEWSLETTERS ,REPORT writing ,RESEARCH funding ,PERIODICAL articles ,IMPACT factor (Citation analysis) - Abstract
Background: The CONsolidated Standards Of Reporting Trials (CONSORT) Statement provides a minimum standard set of items to be reported in published clinical trials; it has received widespread recognition within the biomedical publishing community. This research aims to provide an update on the endorsement of CONSORT by high impact medical journals.Methods: We performed a cross-sectional examination of the online "Instructions to Authors" of 168 high impact factor (2012) biomedical journals between July and December 2014. We assessed whether the text of the "Instructions to Authors" mentioned the CONSORT Statement and any CONSORT extensions, and we quantified the extent and nature of the journals' endorsements of these. These data were described by frequencies. We also determined whether journals mentioned trial registration and the International Committee of Medical Journal Editors (ICMJE; other than in regards to trial registration) and whether either of these was associated with CONSORT endorsement (relative risk and 95 % confidence interval). We compared our findings to the two previous iterations of this survey (in 2003 and 2007). We also identified the publishers of the included journals.Results: Sixty-three percent (106/168) of the included journals mentioned CONSORT in their "Instructions to Authors." Forty-four endorsers (42 %) explicitly stated that authors "must" use CONSORT to prepare their trial manuscript, 38 % required an accompanying completed CONSORT checklist as a condition of submission, and 39 % explicitly requested the inclusion of a flow diagram with the submission. CONSORT extensions were endorsed by very few journals. One hundred and thirty journals (77 %) mentioned ICMJE, and 106 (63 %) mentioned trial registration.Conclusions: The endorsement of CONSORT by high impact journals has increased over time; however, specific instructions on how CONSORT should be used by authors are inconsistent across journals and publishers. Publishers and journals should encourage authors to use CONSORT and set clear expectations for authors about compliance with CONSORT. [ABSTRACT FROM AUTHOR]- Published
- 2016
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9. Best (but oft forgotten) practices: testing for treatment effects in randomized trials by separate analyses of changes from baseline in each group is a misleading approach.
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Bland, Martin and Altman, Douglas G.
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ANALYSIS of covariance ,ANALYSIS of variance ,CONFIDENCE intervals ,DIETETICS research ,PROBABILITY theory ,STATISTICAL hypothesis testing ,STATISTICS ,DATA analysis ,RANDOMIZED controlled trials ,PRE-tests & post-tests ,DESCRIPTIVE statistics - Abstract
Researchers often analyze randomized trials and other comparative studies by separate analysis of changes from baseline in each parallel group. This may be the only analysis presented or it may be in addition to the direct comparison of allocated groups. We illustrate this by reference to 3 recently published nutritional trials. We show why this method of analysis may be highly misleading and may produce type I errors far greater than the 5% that we expect. We recommend direct comparison of means between groups with the use of baseline as a cova-riate if required. [ABSTRACT FROM AUTHOR]
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- 2015
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10. Impact of an online writing aid tool for writing a randomized trial report: the COBWEB (Consort-based WEB tool) randomized controlled trial.
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Barnes, Caroline, Boutron, Isabelle, Giraudeau, Bruno, Porcher, Raphael, Altman, Douglas G., and Ravaud, Philippe
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CLINICAL epidemiology ,EPIDEMIOLOGICAL research ,MEDICAL communication ,HOSPITAL records ,CONFIDENTIAL records ,PUBLISHING ,NEWSLETTERS ,CLINICAL trials ,COMPARATIVE studies ,COMPUTER software ,CONFIDENCE intervals ,EXPERIMENTAL design ,RESEARCH methodology ,MEDICAL cooperation ,MEDICAL writing ,RESEARCH ,T-test (Statistics) ,EVALUATION research ,RANDOMIZED controlled trials ,DESCRIPTIVE statistics ,STANDARDS - Abstract
Background: Incomplete reporting is a frequent waste in research. Our aim was to evaluate the impact of a writing aid tool (WAT) based on the CONSORT statement and its extension for non-pharmacologic treatments on the completeness of reporting of randomized controlled trials (RCTs).Methods: We performed a 'split-manuscript' RCT with blinded outcome assessment. Participants were masters and doctoral students in public health. They were asked to write, over a 4-hour period, the methods section of a manuscript based on a real RCT protocol, with a different protocol provided to each participant. Methods sections were divided into six different domains: 'trial design', 'randomization', 'blinding', 'participants', 'interventions', and 'outcomes'. Participants had to draft all six domains with access to the WAT for a random three of six domains. The random sequence was computer-generated and concealed. For each domain, the WAT comprised reminders of the corresponding CONSORT item(s), bullet points detailing all the key elements to be reported, and examples of good reporting. The control intervention consisted of no reminders. The primary outcome was the mean global score for completeness of reporting (scale 0-10) for all domains written with or without the WAT.Results: Forty-one participants wrote 41 different manuscripts of RCT methods sections, corresponding to 246 domains (six for each of the 41 protocols). All domains were analyzed. For the primary outcome, the mean (SD) global score for completeness of reporting was higher with than without use of the WAT: 7.1 (1.2) versus 5.0 (1.6), with a mean (95 % CI) difference 2.1 (1.5-2.7; P <0.01). Completeness of reporting was significantly higher with the WAT for all domains except for blinding and outcomes.Conclusion: Use of the WAT could improve the completeness of manuscripts reporting the results of RCTs.Trial Registration: Clinicaltrials.gov ( http://clinicaltrials.gov NCT02127567 , registration date first received April 29, 2014). [ABSTRACT FROM AUTHOR]- Published
- 2015
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11. Is the relationship among outcome variables shown in randomized trials?
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Schriger, David L., Cooper, Richelle J., Lopez-O'Sullivan, Ana, Wystrach, Carter, and Altman, Douglas G.
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HEALTH outcome assessment ,RANDOMIZED controlled trials ,INVESTIGATIONAL therapies ,MEDICAL quality control ,PHYSICIAN-patient relations - Abstract
Background: Randomized controlled trials (RCTs) often have more than one primary outcome and frequently have secondary and harm outcomes. Comparison of outcomes between study arms is the primary focus of RCTs, but there are times when the relation between outcomes is important, such as determining whether an intermediate outcome and a clinical outcome have a strong association. We sought to determine how often reports of RCTs depict the relations among outcomes at the individual patient level and, for those studies that use composite outcomes, how often the relations between component elements are depicted. Methods: We selected 20 general, specialty and subspecialty medical journals with high impact factors that publish original clinical research. We identified every RCT in the 2011 and 2012 issues and randomly selected 10 articles per journal. For each article we recorded the number of outcomes, the number of composite outcomes and how often the relations between outcomes or elements of composite outcomes were portrayed. Results: All but 16 of the 200 RCTs had more than one outcome. Thus, outcomes could have been related in 92% of studies, but such relations were only reported in 2 (1%). A total of 33 (17%) investigations measured a composite outcome, 32 of which showed data for each component. None, however, showed cross-tabulation of the components. Conclusions: Readers are rarely shown the relation between outcomes. Mandatory posting of datasets or requirements for detailed appendices would allow readers to see these cross-tabulations, helping future investigators know which outcomes are redundant, which provide unique information and which are most responsive to changes in the independent variables. While not every relationship between outcomes requires depiction, at present such information is seldom portrayed. [ABSTRACT FROM AUTHOR]
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- 2015
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12. Specifying the target difference in the primary outcome for a randomised controlled trial: guidance for researchers.
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Cook, Jonathan A., Hislop, Jenni, Altman, Douglas G., Fayers, Peter, Briggs, Andrew H., Ramsay, Craig R., Norrie, John D., Harvey, Ian M., Buckley, Brian, Fergusson, Dean, Ford, Ian, and Vale, Luke D.
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RANDOMIZED controlled trials ,HEALTH outcome assessment ,RESEARCH ,SAMPLE size (Statistics) ,STATISTICS - Abstract
Background Central to the design of a randomised controlled trial is the calculation of the number of participants needed. This is typically achieved by specifying a target difference and calculating the corresponding sample size, which provides reassurance that the trial will have the required statistical power (at the planned statistical significance level) to identify whether a difference of a particular magnitude exists. Beyond pure statistical or scientific concerns, it is ethically imperative that an appropriate number of participants should be recruited. Despite the critical role of the target difference for the primary outcome in the design of randomised controlled trials, its determination has received surprisingly little attention. This article provides guidance on the specification of the target difference for the primary outcome in a sample size calculation for a two parallel group randomised controlled trial with a superiority question. Methods This work was part of the DELTA (Difference ELicitation in TriAls) project. Draft guidance was developed by the project steering and advisory groups utilising the results of the systematic review and surveys. Findings were circulated and presented to members of the combined group at a face-to-face meeting, along with a proposed outline of the guidance document structure, containing recommendations and reporting items for a trial protocol and report. The guidance and was subsequently drafted and circulated for further comment before finalisation. Results Guidance on specification of a target difference in the primary outcome for a two group parallel randomised controlled trial was produced. Additionally, a list of reporting items for protocols and trial reports was generated. Conclusions Specification of the target difference for the primary outcome is a key component of a randomized controlled trial sample size calculation. There is a need for better justification of the target difference and reporting of its specification. [ABSTRACT FROM AUTHOR]
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- 2015
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13. Impact of peer review on reports of randomised trials published in open peer review journals: retrospective before and after study.
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Hopewell, Sally, Collins, Gary S., Boutron, Isabelle, Ly-Mee Yu, Cook, Jonathan, Shanyinde, Milensu, Wharton, Rose, Shamseer, Larissa, and Altman, Douglas G.
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PROFESSIONAL peer review ,SERIAL publications ,REPORT writing ,RANDOMIZED controlled trials ,RETROSPECTIVE studies ,DESCRIPTIVE statistics ,EVALUATION - Abstract
To investigate the effectiveness of open peer review as a mechanism to improve the reporting of randomised trials published in biomedical journals. Design Retrospective before and after study. Setting BioMed Central series medical journals. Sample 93 primary reports of randomised trials published in BMC-series medical journals in 2012. Main outcome measures Changes to the reporting of methodological aspects of randomised trials in manuscripts after peer review, based on the CONSORT checklist, corresponding peer reviewer reports, the type of changes requested, and the extent to which authors adhered to these requests. Results Of the 93 trial reports, 38% (n=35) did not describe the method of random sequence generation, 54% (n=50) concealment of allocation sequence, 50% (n=46) whether the study was blinded, 34% (n=32) the sample size calculation, 35% (n=33) specification of primary and secondary outcomes, 55% (n=51) results for the primary outcome, and 90% (n=84) details of the trial protocol. The number of changes between manuscript versions was relatively small; most involved adding new information or altering existing information. Most changes requested by peer reviewers had a positive impact on the reporting of the final manuscript--for example, adding or clarifying randomisation and blinding (n=27), sample size (n=15), primary and secondary outcomes (n=16), results for primary or secondary outcomes (n=14), and toning down conclusions to reflect the results (n=27). Some changes requested by peer reviewers, however, had a negative impact, such as adding additional unplanned analyses (n=15). Conclusion Peer reviewers fail to detect important deficiencies in reporting of the methods and results of randomised trials. The number of these changes requested by peer reviewers was relatively small. Although most had a positive impact, some were inappropriate and could have a negative impact on reporting in the final publication. [ABSTRACT FROM AUTHOR]
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- 2014
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14. Methods for Specifying the Target Difference in a Randomised Controlled Trial: The Difference ELicitation in TriAls (DELTA) Systematic Review.
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Hislop, Jenni, Adewuyi, Temitope E., Vale, Luke D., Harrild, Kirsten, Fraser, Cynthia, Gurung, Tara, Altman, Douglas G., Briggs, Andrew H., Fayers, Peter, Ramsay, Craig R., Norrie, John D., Harvey, Ian M., Buckley, Brian, and Cook, Jonathan A.
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RANDOMIZED controlled trials ,CLINICAL medicine research ,PUBLIC health ,MEDICAL research methodology ,CLINICAL trials monitoring - Abstract
: Jonathan Cook and colleagues systematically reviewed the literature for methods of determining the target difference for use in calculating the necessary sample size for clinical trials, and discuss which methods are best for various types of trials. Please see later in the article for the Editors' Summary [ABSTRACT FROM AUTHOR]
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- 2014
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15. Transparent Reporting of Trials Is Essential.
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Altman, Douglas G
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PHYSICIAN practice patterns , *RANDOMIZED controlled trials , *SYSTEMATIC reviews , *PROFESSIONAL peer review , *MEDICAL personnel , *CLINICAL medicine - Abstract
Reports of randomized controlled trials (RCTs) inform the care of future patients and are especially important to clinicians and systematic reviewers. Readers should satisfy themselves that the study methods were sound. Clinicians should consider the relevance to their own patients, both benefits and harms, and absolute as well as relative effects. Trial reports should provide a clear, transparent, and complete report of what was done and what was found. Unfortunately, bad reporting of RCTs is common, which has serious consequences for clinical practice, research, policy making, and ultimately for patients. RCT reports should adhere to the CONSORT Statement, a minimum set of items that should be addressed. Authors, peer reviewers, and editors should all work to ensure that research reports maximize the value derived from the cost and effort of conducting a trial. [ABSTRACT FROM AUTHOR]
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- 2013
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16. Reporting characteristics of non-primary publications of results of randomized trials: a cross-sectional review.
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Hopewell, Sally, Collins, Gary S., Hirst, Allison, Kirtley, Shona, Tajar, Abdelouahid, Gerry, Stephen, and Altman, Douglas G.
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CROSS-sectional method ,STUDY centers ,SUBGROUP analysis (Experimental design) ,RANDOMIZED controlled trials ,DATA extraction - Abstract
Background: For a randomized trial, the primary publication is usually the one which reports the results of the primary outcome and provides consolidated data from all study centers. Other aspects of a randomized trial's findings (that is, non-primary results) are often reported in subsequent publications. Methods: We carried out a cross-sectional review of the characteristics and type of information reported in non-primary reports (n = 69) of randomized trials (indexed in PubMed core clinical journals in 2009) and whether they report pre-specified or exploratory analyses. We also compared consistency of information in non-primary publications with that reported in the primary publication. Results: The majority (n = 56; 81%) of non-primary publications were large, multicenter trials, published in specialty journals. Most reported subgroup analyses (n = 27; 39%), analyzing a specific subgroup of patients from the randomized trial, or reported on secondary outcomes (n = 29; 42%); 19% (n = 13) reported extended follow-up. Less than half reported details of trial registration (n = 30; 43%) or the trial protocol (n = 27; 39%) and in 41% (n = 28) it was unclear from reading the abstract that the report was not the primary publication for the trial. Non-primary publications often analyzed and reported multiple different outcomes (16% reported >20 outcomes) and in 10% (n = 7) it was unclear how many outcomes had actually been assessed; in 42% (n = 29) it was unclear whether the analyses reported were pre-specified or exploratory. Only 39% (n = 27) of non-primary publications described the primary outcome of the randomized trial, 6% (n = 4) reported its numerical results and 9% (n = 6) details of how participants were randomized. Conclusion: Non-primary publications often lack important information about the randomized trial and the type of analyses conducted and whether these were pre-specified or exploratory to enable readers to accurately identify and assess the validity and reliably of the study findings. We provide recommendations for what information authors should include in non-primary reports of randomized trials. [ABSTRACT FROM AUTHOR]
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- 2013
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17. Reporting of Patient-Reported Outcomes in Randomized Trials.
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Calvert, Melanie, Blazeby, Jane, Altman, Douglas G., Revicki, Dennis A., Moher, David, and Brundage, Michael D.
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RANDOMIZED controlled trials ,CLINICAL trial registries ,CLINICAL medicine research ,HEALTH outcome assessment ,MEDICAL care standards ,METHODOLOGY - Abstract
The article offers information on the Consolidated Standards of Reporting Trials patient-reported outcomes (CONSORT-PRO), a new program to improve the reporting of randomized controlled trials. It mentions that the previous program Consolidated Standards of Reporting Trials (CONSORT) lacked guidance on the reporting of patient-reported outcomes (PROs), which are often inadequately reported in trials. It mentions that five new checklist items have been added to the methodological framework of guidelines for randomized controlled trials.
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- 2013
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18. Reporting of Noninferiority and Equivalence Randomized Trials.
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Piaggio, Gilda, Elbourne, Diana R., Pocock, Stuart J., Evans, Stephen J. W., and Altman, Douglas G.
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RANDOMIZED controlled trials ,CLINICAL trials ,RANDOMIZATION (Statistics) ,CLINICAL trial registries ,LISTS ,FLOW charts ,SUBORDINATION (Psychology) ,CLINICAL medicine research - Abstract
The article offers information on the measure taken to handle the problems of inadequate reporting of randomized controlled trials (RCTs). It states that the CONSORT (Consolidated Standards of Reporting Trials) Statement including a checklist and a flow diagram, is developed to help authors improve the reporting of the findings from randomized controlled trials. It mentions that the CONSORT Statement has been extended to further trial designs which include cluster randomization, equivalence trials and recommendations for noninferiority that were made in 2006.
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- 2012
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19. Consort 2010 statement: extension to cluster randomised trials.
- Author
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Campbell, Marion K., Piaggio, Gilda, Elbourne, Diana R., and Altman, Douglas G.
- Subjects
REPORT writing ,RANDOMIZED controlled trials ,EVALUATION - Abstract
The article focuses on the Consolidated Standards of Reporting Trials (CONSORT) statement that was developed to improve the reporting of randomised controlled trials. The statement includes a checklist of items that should be included in the trial report. It was first published in 1996 and was revised in 2001 with a further update in 2010. The standard CONSORT statement focuses on reporting parallel group randomised controlled trials in which individual participants are randomly assigned to study groups. An updated guidance on the reporting of cluster randomised trials based on the 2010 revision of the CONSORT statement and the 2008 CONSORT extension for the reporting of abstracts is provided. It is suggested that routine use of this guidance should lead to improved quality of reporting.
- Published
- 2012
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20. CONSORT 2010 explanation and elaboration: Updated guidelines for reporting parallel group randomised trials.
- Author
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Moher, David, Hopewell, Sally, Schulz, Kenneth F., Montori, Victor, Gøtzsche, Peter C., Devereaux, P.J., Elbourne, Diana, Egger, Matthias, and Altman, Douglas G.
- Subjects
GUIDELINES ,RANDOMIZED controlled trials ,METHODOLOGY ,SYSTEMATIC reviews ,FLOW charts ,MEDICAL statistics - Abstract
Abstract: Overwhelming evidence shows the quality of reporting of randomised controlled trials (RCTs) is not optimal. Without transparent reporting, readers cannot judge the reliability and validity of trial findings nor extract information for systematic reviews. Recent methodological analyses indicate that inadequate reporting and design are associated with biased estimates of treatment effects. Such systematic error is seriously damaging to RCTs, which are considered the gold standard for evaluating interventions because of their ability to minimise or avoid bias. A group of scientists and editors developed the CONSORT (Consolidated Standards of Reporting Trials) statement to improve the quality of reporting of RCTs. It was first published in 1996 and updated in 2001. The statement consists of a checklist and flow diagram that authors can use for reporting an RCT. Many leading medical journals and major international editorial groups have endorsed the CONSORT statement. The statement facilitates critical appraisal and interpretation of RCTs. During the 2001 CONSORT revision, it became clear that explanation and elaboration of the principles underlying the CONSORT statement would help investigators and others to write or appraise trial reports. A CONSORT explanation and elaboration article was published in 2001 alongside the 2001 version of the CONSORT statement. After an expert meeting in January 2007, the CONSORT statement has been further revised and is published as the CONSORT 2010 Statement. This update improves the wording and clarity of the previous checklist and incorporates recommendations related to topics that have only recently received recognition, such as selective outcome reporting bias. This explanatory and elaboration document—intended to enhance the use, understanding, and dissemination of the CONSORT statement—has also been extensively revised. It presents the meaning and rationale for each new and updated checklist item providing examples of good reporting and, where possible, references to relevant empirical studies. Several examples of flow diagrams are included. The CONSORT 2010 Statement, this revised explanatory and elaboration document, and the associated website (www.consort-statement.org) should be helpful resources to improve reporting of randomised trials. [Copyright &y& Elsevier]
- Published
- 2012
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21. Developing core outcome sets for clinical trials: issues to consider.
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Williamson, Paula R., Altman, Douglas G., Blazeby, Jane M., Clarke, Mike, Devane, Declan, Gargon, Elizabeth, and Tugwell, Peter
- Subjects
- *
RANDOMIZED controlled trials , *MEDICAL care , *CLINICAL medicine , *MEDICAL experimentation on humans , *MEDICAL research - Abstract
The selection of appropriate outcomes or domains is crucial when designing clinical trials in order to compare directly the effects of different interventions in ways that minimize bias. If the findings are to influence policy and practice then the chosen outcomes need to be relevant and important to key stakeholders including patients and the public, health care professionals and others making decisions about health care. There is a growing recognition that insufficient attention has been paid to the outcomes measured in clinical trials. These issues could be addressed through the development and use of an agreed standardized collection of outcomes, known as a core outcome set, which should be measured and reported, as a minimum, in all trials for a specific clinical area. Accumulating work in this area has identified the need for general guidance on the development of core outcome sets. Key issues to consider in the development of a core outcome set include its scope, the stakeholder groups to involve, choice of consensus method and the achievement of a consensus. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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- View/download PDF
22. The Cochrane Collaboration's tool for assessing risk of bias in randomised trials.
- Author
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Higgins, Julian P. T., Altman, Douglas G., Gtzsche, Peter C., Jni, Peter, Moher, David, Oxman, Andrew D., Savović, Jelena, Schulz, Kenneth F., Weeks, Laura, and Sterne, Jonathan A. C.
- Subjects
- *
INFORMATION storage & retrieval systems , *MEDICAL databases , *EXPERIMENTAL design , *FOCUS groups , *RESEARCH methodology , *RESEARCH funding , *RISK assessment , *SOUND recordings , *RANDOMIZED controlled trials , *RESEARCH bias , *EVALUATION ,RESEARCH evaluation - Abstract
The article analyzes several issues related to design, conduct, analysis, and reporting of randomised trials and the efficacy of the tool developed by the not-for-profit organization Cochrane Collaboration for assessing risk of bias so the research process can be made clearer and more accurate. It is reported that, the situation of underestimation or overestimation may arise in the presence of flaws in the design, conduct, analysis, and reporting. It is reported that, the tool developed by the organization covers six domains of bias including, selection bias, performance bias, and detection bias.
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- 2011
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23. CONSORT 2010 Statement: Updated Guidelines for Reporting Parallel Group Randomized Trials.
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Schulz, Kenneth F., Altman, Douglas G., and Moher, David
- Subjects
- *
RANDOMIZED controlled trials , *GUIDELINES , *EXPERT evidence , *RESEARCH methodology , *STANDARDS ,RESEARCH evaluation - Abstract
The CONSORT (Consolidated Standards of Reporting Trials) statement is used worldwide to improve the reporting of randomized, controlled trials. Schulz and colleagues describe the latest version, CONSORT 2010, which updates the reporting guideline based on new methodological evidence and accumulating experience. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
24. Reporting and Interpretation of Randomized Controlled Trials With Statistically Nonsignificant Results for Primary Outcomes.
- Author
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Boutron, Isabelle, Dutton, Susan, Ravaud, Philippe, and Altman, Douglas G.
- Subjects
MEDICAL publishing ,RANDOMIZED controlled trials ,MEDLINE ,MEDICAL research ,CLINICAL trial registries ,RESEARCH bias - Abstract
The article discusses a study which identified the nature and frequency of distorted presentation in published reports of randomized controlled trials (RCTs) with statistically nonsignificant results for primary outcomes. The researchers analyzed data from MEDLINE through PubMed using the Cochrane Highly Sensitive Search Strategy to determine RCTs published in December 2006. It was concluded by the researchers that the reporting and interpretation of findings was inconsistent with the results in the representative sample of RCTs.
- Published
- 2010
- Full Text
- View/download PDF
25. CONSORT 2010 Statement.
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Schuk, Kenneth F., Altman, Douglas G., and Moher, David
- Subjects
- *
RANDOMIZED controlled trials , *CLINICAL trials , *EVALUATION of medical care , *STANDARDS , *CLINICAL medicine - Abstract
In this article the author discusses the attributes of Consolidated Standards of Reporting Trials 2010 (CONSORT 2010). He mentions that randomized controlled trials when properly designed and reported is important in the evaluation of health care interventions. He says that CONSORT 2010 provides guidance in reporting all controlled trials with the focus on the most common type. He also cites that with CONSORT 2010, a rigid structure for reporting randomized trials is again missed out.
- Published
- 2010
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- View/download PDF
26. Reporting on covariate adjustment in randomised controlled trials before and after revision of the 2001 CONSORT statement: a literature review.
- Author
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Ly-Mee Yu, An-Wen Chan, Hopewell, Sally, Deeks, Jonathan J., and Altman, Douglas G.
- Subjects
RANDOMIZED controlled trials ,CLINICAL medicine research ,CLINICAL trial registries ,PROCEDURE manuals ,MEDICAL care - Abstract
Objectives: To evaluate the use and reporting of adjusted analysis in randomised controlled trials (RCTs) and compare the quality of reporting before and after the revision of the CONSORT Statement in 2001. Design: Comparison of two cross sectional samples of published articles. Data Sources: Journal articles indexed on PubMed in December 2000 and December 2006. Study Selection: Parallel group RCTs with a full publication carried out in humans and published in English Main outcome measures: Proportion of articles reported adjusted analysis; use of adjusted analysis; the reason for adjustment; the method of adjustment and the reporting of adjusted analysis results in the main text and abstract. Results: In both cohorts, 25% of studies reported adjusted analysis (84/355 in 2000 vs 113/422 in 2006). Compared with articles reporting only unadjusted analyses, articles that reported adjusted analyses were more likely to specify primary outcomes, involve multiple centers, perform stratified randomization, be published in general medical journals, and recruit larger sample sizes. In both years a minority of articles explained why and how covariates were selected for adjustment (20% to 30%). Almost all articles specified the statistical methods used for adjustment (99% in 2000 vs 100% in 2006) but only 5% and 10%, respectively, reported both adjusted and unadjusted results as recommended in the CONSORT guidelines. Conclusion: There was no evidence of change in the reporting of adjusted analysis results five years after the revision of the CONSORT Statement and only a few articles adhered fully to the CONSORT recommendations. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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- View/download PDF
27. Reporting methods in studies developing prognostic models in cancer: a review.
- Author
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Mallett, Susan, Royston, Patrick, Dutton, Susan, Waters, Rachel, and Altman, Douglas G.
- Subjects
PROGNOSTIC tests ,STATISTICS ,RANDOMIZED controlled trials ,MULTIVARIATE analysis ,PSYCHOLOGICAL tests - Abstract
Background: Development of prognostic models enables identification of variables that are influential in predicting patient outcome and the use of these multiple risk factors in a systematic, reproducible way according to evidence based methods. The reliability of models depends on informed use of statistical methods, in combination with prior knowledge of disease. We reviewed published articles to assess reporting and methods used to develop new prognostic models in cancer. Methods: We developed a systematic search string and identified articles from PubMed. Forty-seven articles were included that satisfied the following inclusion criteria: published in 2005; aiming to predict patient outcome; presenting new prognostic models in cancer with outcome time to an event and including a combination of at least two separate variables; and analysing data using multivariable analysis suitable for time to event data. Results: In 47 studies, prospective cohort or randomised controlled trial data were used for model development in only 33% (15) of studies. In 30% (14) of the studies insufficient data were available, having fewer than 10 events per variable (EPV) used in model development. EPV could not be calculated in a further 40% (19) of the studies. The coding of candidate variables was only reported in 68% (32) of the studies. Although use of continuous variables was reported in all studies, only one article reported using recommended methods of retaining all these variables as continuous without categorisation. Statistical methods for selection of variables in the multivariate modelling were often flawed. A method that is not recommended, namely, using statistical significance in univariate analysis as a pre-screening test to select variables for inclusion in the multivariate model, was applied in 48% (21) of the studies. Conclusions: We found that published prognostic models are often characterised by both use of inappropriate methods for development of multivariable models and poor reporting. In addition, models are limited by the lack of studies based on prospective data of sufficient sample size to avoid overfitting. The use of poor methods compromises the reliability of prognostic models developed to provide objective probability estimates to complement clinical intuition of the physician and guidelines. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
28. Comparison of Registered and Published Primary Outcomes in Randomized Controlled Trials.
- Author
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Mathieu, Sylvain, Boutron, Isabelle, Moher, David, Altman, Douglas G., and Ravaud, Philippe
- Subjects
RANDOMIZED controlled trials ,CARDIAC research ,RHEUMATOLOGY ,GASTROENTEROLOGY ,MEDICAL literature ,CLINICAL trials - Abstract
The article discusses a study which compared the registered and published primary outcome of randomized controlled trials (RCT). Study authors reviewed MEDLINE via PubMed to search for RCT reports in cardiology, rheumatology and gastroenterology that were indexed in 2008 in 10 general medical and specialty journals. They found that 45.5 percent of the trials were adequately registered, while 27.6 percent published reports lack trial registration. They also noted that 31 percent of trials with adequate registration showed some discrepancies between the outcomes registered and outcomes published. Study authors concluded that selective outcome reporting is prevalent in RCT.
- Published
- 2009
- Full Text
- View/download PDF
29. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement.
- Author
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Moher, David, Liberati, Alessandro, Tetzlaff, Jennifer, and Altman, Douglas G.
- Subjects
CLINICAL trial registries ,RANDOMIZED controlled trials ,META-analysis ,SYSTEMATIC reviews ,CLINICAL medicine research ,MEDICAL research - Abstract
The article offers information on the changes made on Quality of Reporting of Meta-analyses (QUORUM), the guidelines for the meta-analysis of randomized controlled trials. QUORUM was revised and was changed to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) during a meeting in Ottawa in June 2005, which was participated by clinicians, review authors, medical editors, a consumer and methodologists. The changes were made to address the conceptual and practical advances in the science of systematic reviews. Efforts to endorse and explain PRISMA are also cited.
- Published
- 2009
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- View/download PDF
30. Towards agreement on best practice for publishing raw clinical trial data.
- Author
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Hrynaszkiewicz, Iain and Altman, Douglas G.
- Subjects
- *
CLINICAL trials , *RANDOMIZED controlled trials , *MEDICAL education , *PERIODICAL publishing , *INFORMATION resources - Abstract
Many research-funding agencies now require open access to the results of research they have funded, and some also require that researchers make available the raw data generated from that research. Similarly, the journal Trials aims to address inadequate reporting in randomised controlled trials, and in order to fulfil this objective, the journal is working with the scientific and publishing communities to try to establish best practice for publishing raw data from clinical trials in peerreviewed biomedical journals. Common issues encountered when considering raw data for publication include patient privacy - unless explicit consent for publication is obtained - and ownership, but agreed-upon policies for tackling these concerns do not appear to be addressed in the guidance or mandates currently established. Potential next steps for journal editors and publishers, ethics committees, research-funding agencies, and researchers are proposed, and alternatives to journal publication, such as restricted access repositories, are outlined. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
31. Design, analysis, and presentation of crossover trials.
- Author
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Mills, Edward J., An-Wen Chan, Ping Wu, Vail, Andy, Guyatt, Gordon H., and Altman, Douglas G.
- Subjects
CROSSOVER trials ,CLINICAL trials ,STATISTICAL sampling ,RANDOMIZED controlled trials ,THERAPEUTICS - Abstract
Objective: Although crossover trials enjoy wide use, standards for analysis and reporting have not been established. We reviewed methodological aspects and quality of reporting in a representative sample of published crossover trials. Methods: We searched MEDLINE for December 2000 and identified all randomized crossover trials. We abstracted data independently, in duplicate, on 14 design criteria, 13 analysis criteria, and 14 criteria assessing the data presentation. Results: We identified 526 randomized controlled trials, of which 116 were crossover trials. Trials were drug efficacy (48%), pharmacokinetic (28%), and nonpharmacologic (30%). The median sample size was 15 (interquartile range 8-38). Most (72%) trials used 2 treatments and had 2 periods (64%). Few trials reported allocation concealment (17%) or sequence generation (7%). Only 20% of trials reported a sample size calculation and only 31% of these considered pairing of data in the calculation. Carry-over issues were addressed in 29% of trial's methods. Most trials reported and defended a washout period (70%). Almost all trials (93%) tested for treatment effects using paired data and also presented details on by-group results (95%). Only 29% presented CIs or SE so that data could be entered into a meta-analysis. Conclusion: Reports of crossover trials frequently omit important methodological issues in design, analysis, and presentation. Guidelines for the conduct and reporting of crossover trials might improve the conduct and reporting of studies using this important trial design. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
32. Discrepancies in sample size calculations and data analyses reported in randomised trials: comparison of publications with protocols.
- Author
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An-Wen Chan, Hróbjartsson, Asbjørn, Jørgensen, Karsten J., Gøtzsche, Peter C., and Altman, Douglas G.
- Subjects
COHORT analysis ,RANDOMIZED controlled trials ,STATISTICS ,QUANTITATIVE research ,SAMPLE size (Statistics) ,EVALUATION of clinical trials - Abstract
Objective To evaluate how often sample size calculations and methods of statistical analysis are pre-specified or changed in randomised trials. Design Retrospective cohort study. Data source Protocols and journal publications of published randomised parallel group trials initially approved in 1994-5 by the scientific-ethics committees for Copenhagen and Frederiksberg, Denmark (n=70). Main outcome measure Proportion of protocols and publications that did not provide key information about sample size calculations and statistical methods; proportion of trials with discrepancies between information presented in the protocol and the publication. Results Only 11/62 trials described existing sample size calculations fully and consistently in both the protocol and the publication. The method of handling protocol deviations was described in 37 protocols and 43 publications. The method of handling missing data was described in 16 protocols and 49 publications. 39/49 protocols and 42/43 publications reported the statistical test used to analyse primary outcome measures. Unacknowledged discrepancies between protocols and publications were found for sample size calculations (18/34 trials), methods of handling protocol deviations (19/43) and missing data (39/49), primary outcome analyses (25/42), subgroup analyses (25/25), and adjusted analyses (23/28). Interim analyses were described in 13 protocols but mentioned in only five corresponding publications. Conclusion When reported in publications, sample size calculations and statistical methods were often explicitly discrepant with the protocol or not pre-specified. Such amendments were rarely acknowledged in the trial publication. The reliability of trial reports cannot be assessed without having access to the full protocols. [ABSTRACT FROM AUTHOR]
- Published
- 2008
33. Improving the reporting of pragmatic trials: an extension of the CONSORT statement.
- Author
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Zwarenstein, Merrick, Treweek, Shaun, Gagnier, Joel J., Altman, Douglas G., Tunis, Sean, Haynes, Brian, Oxman, Andrew D., and Moher, David
- Subjects
GUIDELINES ,RANDOMIZED controlled trials ,CLINICAL trial registries ,RESEARCH bias ,MEDICAL research ,MEDICAL care - Abstract
The article provides an extension to the Consolidated Standards of Reporting Trials (CONSORT) guidance with guidance for reporting pragmatic trials. The authors note that randomised controlled trials minimise the risk of bias when conducted properly. The need to clearly report trial results is addressed. The applicability of the trial results to practice is addressed. A table listing the differences between explanatory and pragmatic attitudes is included. A checklist of items for reporting pragmatic trials is presented including background, methods, participants, interventions, and objectives of the trials.
- Published
- 2008
34. Systematic Review of the Empirical Evidence of Study Publication Bias and Outcome Reporting Bias.
- Author
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Dwan, Kerry, Altman, Douglas G., Arnaiz, Juan A., Bloom, Jill, Chan, An-Wen, Cronin, Eugenia, Decullier, Evelyne, Easterbrook, Philippa J., Von Elm, Erik, Gamble, Carrol, Ghersi, Davina, Ioannidis, John P. A., Simes, John, and Williamson, Paula R.
- Subjects
- *
META-analysis , *EMPIRICAL research , *DECISION making , *PUBLICATIONS , *PUBLICATION bias , *RANDOMIZED controlled trials , *MEDICAL protocols - Abstract
Background: The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias has been recognised as a potential threat to the validity of meta-analysis and can make the readily available evidence unreliable for decision making. Until recently, outcome reporting bias has received less attention. Methodology/Principal Findings: We review and summarise the evidence from a series of cohort studies that have assessed study publication bias and outcome reporting bias in randomised controlled trials. Sixteen studies were eligible of which only two followed the cohort all the way through from protocol approval to information regarding publication of outcomes. Eleven of the studies investigated study publication bias and five investigated outcome reporting bias. Three studies have found that statistically significant outcomes had a higher odds of being fully reported compared to nonsignificant outcomes (range of odds ratios: 2.2 to 4.7). In comparing trial publications to protocols, we found that 40-62% of studies had at least one primary outcome that was changed, introduced, or omitted. We decided not to undertake metaanalysis due to the differences between studies. Conclusions: Recent work provides direct empirical evidence for the existence of study publication bias and outcome reporting bias. There is strong evidence of an association between significant results and publication; studies that report positive or significant results are more likely to be published and outcomes that are statistically significant have higher odds of being fully reported. Publications have been found to be inconsistent with their protocols. Researchers need to be aware of the problems of both types of bias and efforts should be concentrated on improving the reporting of trials. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
35. Improving the completeness and transparency of reports of randomized trials in oral health: The CONSORT Statement.
- Author
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NEEDLEMAN, IAN, WORTHING, HELEN, MOHER, DAVID, SCHULZ, KEN, and ALTMAN, DOUGLAS G.
- Subjects
RANDOMIZED controlled trials ,ORAL hygiene ,DENTISTRY ,CLINICAL trial registries ,MEDICAL periodicals - Abstract
Purpose: Randomized trials provide essential evidence of the effect of interventions in oral health. Such trials need to be appraised by readers in order to decide whether to incorporate new findings into clinical practice and policy in a timely manner. The CONSORT (Consolidated Standards of Reporting of Trials) Statement is a guidance to facilitate reporting of randomized controlled trials (RCTs) and was first introduced in 1996. The purpose of this article is to highlight the importance of rigorous reporting of trials in oral health and to discuss the impact of CONSORT on trial reporting. Results: Empirical studies demonstrate that key aspects of trial methods influence the size of estimates of studied interventions and bias is a plausible mechanism for some of this effect. Complete and transparent reporting of these methods allows appraisal of the value of trials to be undertaken and the potential for bias to be estimated. Systematic reviews have shown that the reported quality of trials in dentistry is poor, thus hindering the understanding of the value of individual trials. Since 1996, CONSORT has been adopted by hundreds of medical journals, international editorial groups, and five dental journals. A systematic review has shown that the quality of reporting of trials improves in journals that have adopted this guidance, although with significant variation, most likely due to differing levels of editorial adherence to it. [ABSTRACT FROM AUTHOR]
- Published
- 2008
36. CONSORT for Reporting Randomized Controlled Trials in Journal and Conference Abstracts: Explanation and Elaboration.
- Author
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Hopewell, Sally, Clarke, Mike, Moher, David, Wager, Elizabeth, Middleton, Philippa, Altman, Douglas G., and Schulz, Kenneth F.
- Subjects
CLINICAL trials ,RANDOMIZED controlled trials ,MEDICAL experimentation on humans ,CLINICAL medicine research ,CLINICAL pharmacology ,MEDICAL personnel - Abstract
The authors extend the CONSORT Statement to develop a minimum list of essential items to consider when reporting the results of a randomized trial in any journal or conference abstract. [ABSTRACT FROM AUTHOR]
- Published
- 2008
37. Linked publications from a single trial: a thread of evidence.
- Author
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Altman, Douglas G., Furberg, Curt D., Grimshaw, Jeremy M., and Shanahan, Daniel R.
- Subjects
- *
RANDOMIZED controlled trials , *DIGITAL Object Identifiers , *PUBLICATIONS , *RESEARCH , *ORGANIZATIONAL transparency - Abstract
An editorial is presented on providing all the information related to health related randomized controlled trials and scientific research. Topics discussed include concerns related to publications and the original study despite of transparency in reporting research, multiple publications of single clinical trial and discussion on how to build the digital-object identifier.
- Published
- 2014
- Full Text
- View/download PDF
38. Resources for authors of reports of randomized trials: harnessing the wisdom of authors, editors, and readers.
- Author
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Moher, David, Hopewell, Sally, Schulz, Kenneth F., and Altman, Douglas G.
- Subjects
CLINICAL medicine research ,DATABASES ,RANDOMIZED controlled trials ,AUTHOR-reader relationships ,AUTHORSHIP - Abstract
The CONSORT Statement was developed to help authors improve the quality of reporting randomized trials. To augment the statement we published the CONSORT explanation and elaboration paper which included at least one example of good reporting for each CONSORT checklist item. We are developing a comprehensive database of examples of good reporting for each checklist item to take advantage of the breadth and variety of trials familiar to authors and readers globally. We invite authors, editors, and readers worldwide to nominate examples of well reported items for the database. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
39. CONSORT 2010 changes and testing blindness in RCTs.
- Author
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Schulz, Kenneth F., Altman, Douglas G., Moher, David, and Fergusson, Dean
- Subjects
- *
CLINICAL trial registries , *RANDOMIZED controlled trials , *BLIND experiment , *RESEARCH methodology , *EXPERIMENTAL design , *MEDICAL research methodology - Abstract
The authors comment on the changes stipulated in the CONSORT 2010 Statement for randomised trials. They explain the decision to eliminate how the success of blinding might have been evaluated, which counters the views expressed by many investigators. They discuss changes to the blinding item in the updated CONSORT 2010, such as the need for investigators to maintain the integrity of blinding. The authors also cite interpretational and measurement difficulties as the factors that question the usefulness of tests of blinding.
- Published
- 2010
- Full Text
- View/download PDF
40. The influence of CONSORT on the quality of reporting of randomised controlled trials: an updated review.
- Author
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Turner, Lucy, Moher, David, Shamseer, Larissa, Weeks, Laura, Peters, Jodi, Plint, Amy, Altman, Douglas G., and Schulz, Kenneth F.
- Subjects
RANDOMIZED controlled trials - Abstract
An abstract of the article "The influence of CONSORT on the quality of reporting of randomised controlled trials: an updated review," by Lucy Turner and colleagues, is presented.
- Published
- 2011
- Full Text
- View/download PDF
41. Response to "Best (but oft forgotten) practices: testing for treatment effects in randomized trials by separate analyses of changes from baseline in each group is a misleading approach".
- Author
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Stanhope, Kimber L., Havel, Peter J., Bland, J. Martin, and Altman, Douglas G.
- Subjects
DIETETICS research ,STATISTICS ,DATA analysis ,RANDOMIZED controlled trials - Abstract
The article presents the authors' reply to the use of their study as the first example of how not to compare group means with each other as they point out that their conclusions were not based on within-group comparisons. They note that they were instructed by the editor to replace their tables describing the between-group differences to the supplement with tables that showed only the within-group changes with P values. They indicate their intent to clarify and not to mislead.
- Published
- 2016
- Full Text
- View/download PDF
42. Association between randomised trial evidence and global burden of disease: cross sectional study (Epidemiological Study of Randomized Trials—ESORT).
- Author
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Emdin, Connor A., Odutayo, Ayodele, Hsiao, Allan J., Shakir, Mubeen, Hopewell, Sally, Rahimi, Kazem, and Altman, Douglas G.
- Subjects
PUBLISHING ,DISEASES ,PROBABILITY theory ,STATISTICS ,DATA analysis ,RANDOMIZED controlled trials ,CROSS-sectional method ,DESCRIPTIVE statistics ,EVALUATION - Abstract
The article discusses research which examined the association between the number of published randomised controlled trials and the global burden of disease. Topics covered include the poor association between total disability adjusted life years and the number of randomised trials, the fewer trials found for diseases for which the burden was located in low income regions and the few trials discovered for high income type diseases.
- Published
- 2015
- Full Text
- View/download PDF
43. Presentation of continuous outcomes in randomised trials: an observational study.
- Author
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Schriger, David L., Savage, Dan F., and Altman, Douglas G.
- Subjects
SCIENTIFIC observation ,HEALTH outcome assessment ,RANDOMIZED controlled trials ,TREATMENT effectiveness ,CROSS-sectional method ,DESCRIPTIVE statistics ,EVALUATION - Abstract
The article reports a study which was conducted to determine the percentage of available data for continuous primary outcomes presented in randomised trials published in high impact factor medical journals. The results revealed that when adjusted for the number of patients in the trial, studies report a median 3.5 percent of the available data for the best reported primary outcome. This indicates that only a small fraction of the available data is reported.
- Published
- 2013
- Full Text
- View/download PDF
44. Heart Rate and Rhythm and the Benefit of Beta-Blockers in Patients With Heart Failure.
- Author
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Kotecha, Dipak, Flather, Marcus D., Altman, Douglas G., Holmes, Jane, Rosano, Giuseppe, Wikstrand, John, Packer, Milton, Coats, Andrew J.S., Manzano, Luis, Böhm, Michael, van Veldhuisen, Dirk J., Andersson, Bert, Wedel, Hans, von Lueder, Thomas G., Rigby, Alan S., Hjalmarson, Åke, Kjekshus, John, Cleland, John G.F., and Beta-Blockers in Heart Failure Collaborative Group
- Subjects
- *
HEART failure , *HEART beat , *ADRENERGIC beta blockers , *SINUS arrhythmia , *MORTALITY - Abstract
Background: The relationship between mortality and heart rate remains unclear for patients with heart failure with reduced ejection fraction in either sinus rhythm or atrial fibrillation (AF).Objectives: This analysis explored the prognostic importance of heart rate in patients with heart failure with reduced ejection fraction in randomized controlled trials comparing beta-blockers and placebo.Methods: The Beta-Blockers in Heart Failure Collaborative Group performed a meta-analysis of harmonized individual patient data from 11 double-blind randomized controlled trials. The primary outcome was all-cause mortality, analyzed with Cox proportional hazard ratios (HR) modeling heart rate measured at baseline and approximately 6 months post-randomization.Results: A higher heart rate at baseline was associated with greater all-cause mortality for patients in sinus rhythm (n = 14,166; adjusted HR: 1.11 per 10 beats/min; 95% confidence interval [CI]: 1.07 to 1.15; p < 0.0001) but not in AF (n = 3,034; HR: 1.03 per 10 beats/min; 95% CI: 0.97 to 1.08; p = 0.38). Beta-blockers reduced ventricular rate by 12 beats/min in both sinus rhythm and AF. Mortality was lower for patients in sinus rhythm randomized to beta-blockers (HR: 0.73 vs. placebo; 95% CI: 0.67 to 0.79; p < 0.001), regardless of baseline heart rate (interaction p = 0.35). Beta-blockers had no effect on mortality in patients with AF (HR: 0.96, 95% CI: 0.81 to 1.12; p = 0.58) at any heart rate (interaction p = 0.48). A lower achieved resting heart rate, irrespective of treatment, was associated with better prognosis only for patients in sinus rhythm (HR: 1.16 per 10 beats/min increase, 95% CI: 1.11 to 1.22; p < 0.0001).Conclusions: Regardless of pre-treatment heart rate, beta-blockers reduce mortality in patients with heart failure with reduced ejection fraction in sinus rhythm. Achieving a lower heart rate is associated with better prognosis, but only for those in sinus rhythm. [ABSTRACT FROM AUTHOR]- Published
- 2017
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45. Randomized Controlled Trials With Statistically Nonsignificant Results.
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Allison, David B., Cope, Mark B., Boutron, Isabelle, Ravaud, Philippe, and Altman, Douglas G.
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LETTERS to the editor ,RANDOMIZED controlled trials - Abstract
A letter and a response to a letter to the editor is presented which discussed the inappropriate use of statistically nonsignificant results in public reports of randomized controlled trials.
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- 2010
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46. Small study effects in meta-analyses of osteoarthritis trials: meta-epidemiological study.
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Nüesch, Eveline, Trelle, Sven, Reichenbach, Stephan, Rutjes, Anne W. S., Tschannen, Beatrice, Altman, Douglas G., Egger, Matthias, and Jüni, Peter
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OSTEOARTHRITIS ,META-analysis ,RANDOMIZED controlled trials ,KNEE diseases ,HIP joint diseases ,MEDICAL research evaluation - Abstract
The article focuses on a meta-analysis which investigated the extent to which small study effects influence the results of clinical osteoarthritis research. The meta-analysis included 153 randomised controlled trials which compared therapeutic interventions with placebo in treating pain associated with knee or hip osteoarthritis. Study authors also concluded that small study effects affect the results of meta-analyses in osteoarthritis research.
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- 2010
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47. The quality of reports of randomised trials in 2000 and 2006: comparative study of articles indexed in PubMed.
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Hopewell, Sally, Dutton, Susan, Ly-Mee Yu, An-Wen Chan, and Altman, Douglas G.
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RESEARCH ,REPORTING of diseases ,CLINICAL trials ,RANDOMIZED controlled trials ,DISCLOSURE ,GUIDELINES - Abstract
The article offers information on a study which examined improvements in the documentation of methodological details in reports of randomized trials following the publication of the Consolidated Standards of Reporting Trials (CONSORT) Statement in 2001. It mentions that CONSORT Statement offers guidelines how to prepare articles disclosing the findings of a randomized trials. The main outcome measure was defined as the proportion of methodological items disclosed in randomized trials from 2000 to 2006. Presented in details are the research findings.
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- 2010
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48. The CONSORT statement: revised recommendations for improving the quality of reports of parallel group randomized trials.
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Moher, David, Schulz, Kenneth F., Altman, Douglas G., Moher, D, Schulz, K F, Altman, D G, and CONSORT
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CLINICAL trial registries ,RANDOMIZED controlled trials ,CLINICAL medicine research ,RELIABILITY (Personality trait) ,FLOW charts - Abstract
To comprehend the results of a randomized controlled trial (RCT), readers must understand its design, conduct, analysis and interpretation. That goal can only be achieved through complete transparency from authors. Despite several decades of educational efforts, the reporting of RCTs needs improvement. Investigators and editors developed the original CONSORT (Consolidated Standards of Reporting Trials) statement to help authors improve reporting by using a checklist and flow diagram. The revised CONSORT statement presented in this paper incorporates new evidence and addresses some criticisms of the original statement.The checklist items pertain to the content of the Title, Abstract, Introduction, Methods, Results and Discussion. The revised checklist includes 22-items selected because empirical evidence indicates that not reporting the information is associated with biasedestimates of treatment effect or the information is essential to judge the reliability or relevance of the findings. We intended the flow diagram to depict the passage of participants through an RCT. The revised flow diagram depicts information from four stages of a trial (enrollment, intervention allocation, follow-up, and analysis). The diagram explicitly includes the number of participants, for each intervention group, included in the primary data analysis. Inclusion of these numbers allows the reader to judge whether the authors have performed an intention-to-treat analysis.In sum, the CONSORT statement is intended to improve the reporting of an RCT, enabling readers to understand a trial's conduct and to assess the validity of its results. [ABSTRACT FROM AUTHOR]
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- 2001
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49. Reporting clinical research: Guidance to encourage accurate and transparent research reporting
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Simera, Iveta, Kirtley, Shona, and Altman, Douglas G.
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RANDOMIZED controlled trials , *EPIDEMIOLOGY , *SYSTEMATIC reviews , *ETIOLOGY of diseases , *MEDICAL research , *PUBLIC health - Abstract
Abstract: To encourage accurate, complete, and transparent reporting of research studies we provide a brief overview of generic guidelines for reporting the main types of clinical research: randomised trials, observational studies in epidemiology, and systematic reviews. These and many other guidelines developed to help authors to achieve the highest standards in their research publications are available on the EQUATOR (Enhancing the Quality and Transparency of Health Research) Network website (www.equator-network.org). [Copyright &y& Elsevier]
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- 2012
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50. Bilateral versus Single Internal-Thoracic-Artery Grafts at 10 Years.
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Taggart, David P., Benedetto, Umberto, Gerry, Stephen, Altman, Douglas G., Gray, Alastair M., Lees, Belinda, Gaudino, Mario, Zamvar, Vipin, Bochenek, Andrzej, Buxton, Brian, Choong, Cliff, Clark, Stephen, Deja, Marek, Desai, Jatin, Hasan, Ragheb, Jasinski, Marek, O'Keefe, Peter, Moraes, Fernando, Pepper, John, and Seevanayagam, Siven
- Subjects
- *
CORONARY heart disease surgery , *INTERNAL thoracic artery , *CLINICAL trials , *COMPARATIVE studies , *CORONARY artery bypass , *CORONARY disease , *CAUSES of death , *LONGITUDINAL method , *RESEARCH methodology , *MEDICAL cooperation , *MYOCARDIAL infarction , *RESEARCH , *RESEARCH funding , *STROKE , *SURVIVAL analysis (Biometry) , *EVALUATION research , *RANDOMIZED controlled trials , *TRANSPLANTATION of organs, tissues, etc. - Abstract
Background: Multiple arterial grafts may result in longer survival than single arterial grafts after coronary-artery bypass grafting (CABG) surgery. We evaluated the use of bilateral internal-thoracic-artery grafts for CABG.Methods: We randomly assigned patients scheduled for CABG to undergo bilateral or single internal-thoracic-artery grafting. Additional arterial or vein grafts were used as indicated. The primary outcome was death from any cause at 10 years. The composite of death from any cause, myocardial infarction, or stroke was a secondary outcome.Results: A total of 1548 patients were randomly assigned to undergo bilateral internal-thoracic-artery grafting (the bilateral-graft group) and 1554 to undergo single internal-thoracic-artery grafting (the single-graft group). In the bilateral-graft group, 13.9% of the patients received only a single internal-thoracic-artery graft, and in the single-graft group, 21.8% of the patients also received a radial-artery graft. Vital status was not known for 2.3% of the patients at 10 years. In the intention-to-treat analysis at 10 years, there were 315 deaths (20.3% of the patients) in the bilateral-graft group and 329 deaths (21.2%) in the single-graft group (hazard ratio, 0.96; 95% confidence interval [CI], 0.82 to 1.12; P=0.62). Regarding the composite outcome of death, myocardial infarction, or stroke, there were 385 patients (24.9%) with an event in the bilateral-graft group and 425 patients (27.3%) with an event in the single-graft group (hazard ratio, 0.90; 95% CI, 0.79 to 1.03).Conclusions: Among patients who were scheduled for CABG and had been randomly assigned to undergo bilateral or single internal-thoracic-artery grafting, there was no significant between-group difference in the rate of death from any cause at 10 years in the intention-to-treat analysis. Further studies are needed to determine whether multiple arterial grafts provide better outcomes than a single internal-thoracic-artery graft. (Funded by the British Heath Foundation and others; Current Controlled Trials number, ISRCTN46552265 .). [ABSTRACT FROM AUTHOR]- Published
- 2019
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