640 research outputs found

    A Meta- and Trial Sequential Analysis

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    Objectives Periodontal treatment might reduce adverse pregnancy outcomes. The efficacy of periodontal treatment to prevent preterm birth, low birth weight, and perinatal mortality was evaluated using meta-analysis and trial sequential analysis. Methods An existing systematic review was updated and meta-analyses performed. Risk of bias, heterogeneity, and publication bias were evaluated, and meta-regression performed. Subgroup analysis was used to compare different studies with low and high risk of bias and different populations, i.e., risk groups. Trial sequential analysis was used to assess risk of random errors. Results Thirteen randomized clinical trials evaluating 6283 pregnant women were meta-analyzed. Four and nine trials had low and high risk of bias, respectively. Overall, periodontal treatment had no significant effect on preterm birth (odds ratio [95% confidence interval] 0.79 [0.57-1.10]) or low birth weight (0.69 [0.43-1.13]). Trial sequential analysis demonstrated that futility was not reached for any of the outcomes. For populations with moderate occurrence (<20%) of preterm birth or low birth weight, periodontal treatment was not efficacious for any of the outcomes, and trial sequential analyses indicated that further trials might be futile. For populations with high occurrence (≥20%) of preterm birth and low birth weight, periodontal treatment seemed to reduce the risk of preterm birth (0.42 [0.24-0.73]) and low birth weight (0.32 [0.15-0.67]), but trial sequential analyses showed that firm evidence was not reached. Periodontal treatment did not significantly affect perinatal mortality, and firm evidence was not reached. Risk of bias, but not publication bias or patients’ age modified the effect estimates. Conclusions Providing periodontal treatment to pregnant women could potentially reduce the risks of perinatal outcomes, especially in mothers with high risks. Conclusive evidence could not be reached due to risks of bias, risks of random errors, and unclear effects of confounding. Further randomized clinical trials are required

    Power estimations for non-primary outcomes in randomised clinical trials

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    Objective and methods: It is rare that trialists report power estimations of non-primary outcomes. In the present article, we will describe how to define a valid hierarchy of outcomes in a randomised clinical trial, to limit problems with Type I and Type II errors, using considerations on the clinical relevance of the outcomes and power estimations. Conclusion: Power estimations of non-primary outcomes may guide trialists in classifying non-primary outcomes as secondary or exploratory. The power estimations are simple and if they are used systematically, more appropriate outcome hierarchies can be defined, and trial results will become more interpretable

    Trial sequential analysis for assessing imprecision in GRADE evaluations – protocol for a methodological study

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    Abstract Background: Assessing statistical imprecision of summary estimates is an essential element in evaluating the strength of evidence. The GRADE framework recommends assessing imprecision by confidence intervals (CI) in relation to thresholds of interest and in selected cases to assess the relationship between the acquired information size and the calculated optimal information size (OIS). Trial sequential analysis (TSA) calculates multiplicity-adjusted confidence intervals and can be used to calculate a required information size. In a recent methodological study of 544 systematic reviews and meta-analysis reports of clinical trials with TSA, we gathered data regarding the methods used for grading imprecision, specifically regarding the impact of TSA (the METSA project). The questions regarding GRADE imprecision were initially superficially defined and were substantialized only during the project and in the preparations for this protocol. With this add-on study, we investigate the methods of grading imprecision in the GRADE framework by authors of systematic reviews and meta-analysis reports of clinical trials with TSA. Methods: The outlined methodological study will be pre-planned but designed with knowledge about existing but not yet reviewed data on the study questions. The METSA project was not initially designed for the questions raised in the current study protocol, which warrants a critical review of the collected data. We aim to improve precision and accuracy of the collected data regarding imprecision methodology by a redesign of selected data fields, adding new data fields to the data extraction form and a subsequent revision of the existing data extraction accordingly. For each individual study, we will extract or review data regarding the specified methodology including methods for calculating CI and OIS, and thresholds of interest (definitions of important benefit and/or harm). For each topic, we will assess completeness in transparency of described methods and protocolisation, including coherence with the protocol (if relevant). Results: We will report frequencies of observed methods, lack of transparency, and protocolisation. From data gathered in the METSA project, we will report the proportion of imprecision assessments that may have differed in their conclusions if the results of the TSA had been used. Informed by our findings, we will outline new suggestions on how to grade imprecision using TSA. Conclusion: This protocol outlines a methodological study of methods and reporting characteristics imprecision assessment within the GRADE framework in recent systematic reviews and meta-analysis reports of clinical trials utilising trial sequential analysis

    Melatonin for sleep disorders in children with neurodevelopmental disorders: protocol for a systematic review with meta-analysis and Trial Sequential Analysis of randomised clinical trials

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    INTRODUCTION: Neurodevelopmental disorders are a group of disorders thought to be associated with the functioning of the brain and the nervous system. Children with neurodevelopmental disorders often have sleep-related comorbidities that may negatively affect quality of life for both the children and their families. Melatonin is one of the most used interventions in children with neurodevelopmental disorders and sleep disorders. Previous reviews have investigated the effects of melatonin for sleep disorders in children with neurodevelopmental disorders, but these had important limitations, such as inadequate analysis of adverse effects, small sample sizes and short follow-up. METHODS AND ANALYSIS: This is a protocol for a systematic review with meta-analysis and Trial Sequential Analysis of randomised clinical trials. The protocol is reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols. We will search for published and unpublished trials in the Cochrane Central Register of Controlled Trials, MEDLINE Ovid, Embase Ovid, LILACS, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, PsycINFO, ClinicalTrials.gov and the International Clinical Trials Registry Platform. We will search the databases from their inception without language restrictions. We will also request clinical study reports from regulatory authorities and pharmaceutical companies. Review authors working in pairs will screen reports, extract data and conduct risk of bias assessments using the Cochrane Risk of Bias tool. We will include randomised clinical trials comparing melatonin versus placebo or no intervention for sleep disorders in children with neurodevelopmental disorders. Primary outcomes will be total sleep time and adverse effects. Secondary outcomes will be quality of life of the child and caregivers and sleep onset latency. Data will be analysed using random-effects and fixed-effect meta-analyses. Certainty of evidence will be assessed with Grading of Recommendations, Assessment, Development and Evaluation approach. ETHICS AND DISSEMINATION: Ethical approval was not required for this protocol. The systematic review will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42022337530

    Disclosure of investigators' Recruitment performance in multicenter clinical trials: a further step for research transparency

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    Transparency: A Fundamental Social Obligation for Clinical Research .After 60 years devoted to enhancing the methodology and ethics in clinical research, the last decade has been crucial to the scientific community in refining the transparency on conducting clinical trials (CTs), from their inception to the publication of results. A myriad of articles have been published on the design, conduct, conflicts of interest, reporting, and publication of CTs..

    Prothrombin complex concentrate versus placebo, no intervention, or other interventions in critically bleeding patients associated with oral anticoagulant administration: a protocol for a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis

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    Background: Acute critical bleeding is one of the most feared complications during treatment with oral anticoagulating agents. As more patients undergo treatment with anticoagulating agents, critically bleeding episodes in patients with vitamin K antagonists, thrombin inhibitor, or factor Xa inhibitor-inducted coagulopathy will be encountered frequently by physicians. Hence, an effective treatment capable of reversing the iatrogenic coagulopathy in the acute setting is needed. In randomised clinical trials and observational studies, prothrombin complex concentrate has been reported to be superior to other acute interventions, and many guidelines recommend prothrombin complex concentrate in treatment of critically bleeding patients. The aim of this systematic review is to synthesise the evidence of the effects of prothrombin complex concentrate compared with placebo, no intervention, or other treatment options in critically bleeding patients treated with oral anticoagulants. Methods/design: A comprehensive search for relevant published literature will be undertaken in Cochrane Central Register of Controlled Trials, MEDLINE, Embase, WHO International Clinical Trials Registry Platform, Science Citation Index, regulatory databases, and trial registers. We will include randomised clinical trials comparing prothrombin complex concentrate versus placebo, no intervention, or other interventions in critically bleeding patients with oral anticoagulant-induced coagulopathy. Data extraction and risk of bias assessment will be handled by two independent review authors. Meta-analysis will be performed as recommended by Cochrane Handbook for Systematic Reviews of Interventions, bias will be assessed with domains, and trial sequential analysis will be conducted to control random errors. Certainty will be assessed by GRADE. Discussion: As critical bleeding in patients treated with oral anticoagulants is an increasing problem, an up-to-date systematic review evaluating the benefits and harms of prothrombin complex concentrate is urgently needed. It is the hope that this review will be able to guide best practice in treatment and clinical research of these critically bleeding patients. Systematic review registration: PROSPERO CRD4201808437
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