scholarly journals When poorly conducted systematic reviews and meta-analyses can mislead: a critical appraisal and update of systematic reviews and meta-analyses examining the effects of probiotics in the treatment of functional constipation in children

2019 ◽  
Vol 110 (1) ◽  
pp. 177-195 ◽  
Author(s):  
Rebecca G Harris ◽  
Elizabeth P Neale ◽  
Isabel Ferreira
Keyword(s):  
Systematic Reviews ◽  
Evidence Synthesis ◽  
Weighted Mean Difference ◽  
Treatment Success ◽  
Functional Constipation ◽  
Risk Of Bias ◽  
Current Evidence ◽  
Success Rates ◽  
Defecation Frequency ◽  
Meta Analyses

ABSTRACT Background Recent systematic reviews and meta-analyses on the efficacy of probiotics in the treatment of functional constipation in children have yielded conflicting results. Objectives The aim of this study was to critically review and update the evidence in this field by mapping all the steps involved against those reported in previous reviews, in an attempt to understand the nature of their conflicting results. Methods Four literature databases, trial registries, and citations were searched through December 1, 2018. We included randomized controlled trials (RCTs) that assessed the effects of probiotics compared with placebo or treatment as usual on defecation frequency [bowel movements (BMs)/wk] or treatment success rates in children with functional constipation. Independent reviewers extracted the data and assessed risk of bias in each RCT. Data were pooled with (inverse variance) random-effects models. Results We identified 17 RCTs, of which 14 and 11 provided sufficient data to enable meta-analysis of the effects of probiotics compared with control on defecation frequency (n = 965) or treatment success (n = 835), respectively. When compared to (any) control intervention, probiotics did not significantly increase defecation frequency [weighted mean difference (WMD): 0.28 BMs/wk; 95% CI: −0.12, 0.69; P = 0.165] but were more efficacious in achieving treatment success (RR: 1.24; 95% CI: 1.03, 1.50; P = 0.024). These effects did not differ by type of control (i.e., active or inactive) intervention. However, in analyses confined to the RCTs that were free of high risk of bias (only 5), probiotics did not confer any beneficial effects on defecation frequency (WMD: −0.55 BMs/wk; 95% CI: −1.37, 0.26; P = 0.185) and achievement of treatment success (RR: 1.01; 95% CI: 0.90, 1.13; P = 0.873), compared with control interventions. Conclusions The current evidence thus does not support the use of probiotics as a single or coadjuvant therapy for treatment of functional constipation in children and refutes recently published reviews reporting favorable effects of probiotics. Conflicting findings of previous reviews resulted from methodologic errors, highlighting the susceptibility of evidence synthesis to oversights in study selection, quality assessments, and data extraction and collation. This review was registered at PROSPERO as CRD42019119109.

Remotely Delivered Monitoring and Management of Diabetes-Related Foot Disease: An Overview of Systematic Reviews

2021 ◽  
pp. 193229682110124
Author(s):  
Aaron Drovandi ◽  
Shannon Wong ◽  
Leonard Seng ◽  
Benjamin Crowley ◽  
Chanika Alahakoon ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Systematic Reviews ◽  
Urban Areas ◽  
Meta Analysis ◽  
Risk Of Bias ◽  
Limb Amputation ◽  
Current Evidence ◽  
Or Management ◽  
Foot Disease ◽  
Poor Reporting

Background: Diabetes-related foot disease (DFD) management requires input from multiple healthcare professionals, and has worse outcomes for people living in remote localities by comparison to urban areas. Remotely delivered healthcare may reduce this disparity. This overview summarizes current evidence on the effectiveness, stakeholder perceptions, and cost-effectiveness of remotely delivered healthcare for DFD. Methods: A search of 5 databases was conducted to identify systematic reviews published between January 2000 and June 2020. Eligible reviews were those evaluating remotely delivered monitoring or management of patients at risk of or with active DFD, or clinicians managing these patients. Risk of bias was assessed using the AMSTAR-2 tool. Results: Eight reviews were eligible for inclusion, including 88 primary studies and 8509 participants, of which 36 studies involving 4357 participants evaluated remotely delivered monitoring or management of DFD. Only one review had a low risk of bias, with most reviews demonstrating limited search strategies and poor reporting of participants. Evidence on effectiveness was mixed, with meta-analyses demonstrating long-term ulcer healing and mortality were not significantly different between telehealth and standard care groups, although the lower-limb amputation rate was significantly decreased in one meta-analysis. Perceptions of telehealth by patients and clinicians were generally positive, whilst acknowledging limitations relating to access and use. Cost-effectiveness data were limited, with poor reporting preventing clear conclusions. Conclusions: Remotely delivered healthcare of DFD is well received by patients and clinicians, but its effectiveness is unclear. High quality trials are needed to evaluate the risks and benefits of remotely delivered DFD management.

scholarly journals Consequences of the COVID-19 Syndemic for Nutritional Health: A Systematic Review

Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1168
Author(s):  
Cristian Neira ◽  
Rejane Godinho ◽  
Fabio Rincón ◽  
Rodrigo Mardones ◽  
Janari Pedroso
Keyword(s):  
Systematic Review ◽  
Systematic Reviews ◽  
Preventive Measures ◽  
Physical Contact ◽  
Current Evidence ◽  
Study Objective ◽  
Eating Style ◽  
Healthy Nutrition ◽  
Meta Analyses ◽  
The Impact

Confinement at home, quarantine, and social distancing are some measures adopted worldwide to prevent the spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-Cov-2), which has been generating an important alteration in the routines and qualities of life of people. The impact on health is still being evaluated, and consequences in the nutritional field are not entirely clear. The study objective was to evaluate the current evidence about the impact that preventive measures of physical contact restriction causes in healthy nutrition. A systematic review was carried out according to the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses” PRISMA Group and Cochrane method for rapid systematic reviews. Searching was performed in six electronic databases and evaluated articles published between 2010 and 2020, including among their participants adult subjects who had been exposed to the preventive measures of physical contact restriction. Seven studies met the selection criteria and reported an overall increase in food consumption, weight, Body Mass Index (BMI), and a change in eating style. Findings suggest that healthy nutrition is affected by preventive measures to restrict physical contact as a result of the COVID-19 syndemic.

scholarly journals Polyphenols and Cognition In Humans: An Overview of Current Evidence from Recent Systematic Reviews and Meta-Analyses

2020 ◽  
pp. 1-15
Author(s):  
Daniel Joseph Lamport ◽  
Claire Michelle Williams
Keyword(s):  
Systematic Reviews ◽  
Evidence Base ◽  
Epidemiological Studies ◽  
Cognitive Outcome ◽  
Current Evidence ◽  
Duration Of Treatment ◽  
Current Evidence Base ◽  
Cognitive Benefits ◽  
Meta Analyses ◽  
The Impact

There is increasing interest in the impact of dietary influences on the brain throughout the lifespan, ranging from improving cognitive development in children through to attenuating ageing related cognitive decline and reducing risk of neurodegenerative diseases. Polyphenols, phytochemicals naturally present in a host of fruits, vegetables, tea, cocoa and other foods, have received particular attention in this regard, and there is now a substantial body of evidence from experimental and epidemiological studies examining whether their consumption is associated with cognitive benefits. The purpose of this overview is to synthesise and evaluate the best available evidence from two sources, namely meta-analyses and systematic reviews, in order to give an accurate reflection of the current evidence base for an association between polyphenols and cognitive benefits. Four meta-analyses and thirteen systematic reviews published between 2017–2020 were included, and were categorised according to whether they reviewed specific polyphenol-rich foods and classes or all polyphenols. A requirement for inclusion was assessment of a behavioural cognitive outcome in humans. A clear and consistent theme emerged that whilst there is support for an association between polyphenol consumption and cognitive benefits, this conclusion is tentative, and by no means definitive. Considerable methodological heterogeneity was repeatedly highlighted as problematic such that the current evidence base does not support reliable conclusions relating to efficacy of specific doses, duration of treatment, or sensitivity in specific populations or certain cognitive domains. The complexity of multiple interactions between a range of direct and indirect mechanisms of action is discussed. Further research is required to strengthen the reliability of the evidence base.

scholarly journals CogTale: An online platform for the evaluation, synthesis and dissemination of evidence from cognitive interventions studies

2020 ◽  
Author(s):  
Julieta Sabates ◽  
Sylvie Belleville ◽  
Mary Castellani ◽  
Tzvi Dwolatsky ◽  
Benjamin M. Hampstead ◽  
...  
Keyword(s):  
Systematic Reviews ◽  
Intervention Studies ◽  
Evidence Synthesis ◽  
Research Synthesis ◽  
Cognitive Intervention ◽  
Synthesis Methods ◽  
Data Synthesis ◽  
Advanced Search ◽  
Health Related ◽  
Meta Analyses

Abstract Systematic reviews and meta-analyses are critical in health-related decision making, and are considered the gold standard in research synthesis methods. However, with new trials being regularly published and with the development of increasingly rigorous standards of data synthesis, systematic reviews often require much expertise and long periods of time to be completed. Automation of some of the steps of evidence synthesis productions is a promising improvement in the field, capable of reducing the time and costs associated with the process. This article describes the development and main characteristics of a novel online repository of cognitive intervention studies entitled Cognitive Treatments Article Library and Evaluation (CogTale). The platform is currently in a Beta Release phase, as it is still under development. However, it already contains over 70 studies, and the CogTale team is continuously coding and uploading new studies into the repository. Key features include advanced search options, the capability to generate meta-analyses, and an up-to-date display of relevant published studies.

scholarly journals The development of a new generic risk-of-bias measure for systematic reviews of surveys

Methodology ◽  
2020 ◽  
Vol 16 (4) ◽  
pp. 278-298
Author(s):  
Gabriel Nudelman ◽  
Kathleen Otto
Keyword(s):  
Pilot Study ◽  
Systematic Reviews ◽  
Convergent Validity ◽  
Meta Analysis ◽  
Weighted Kappa ◽  
Risk Of Bias ◽  
Interrater Agreement ◽  
Bias Measure ◽  
Meta Analyses ◽  
Initial List

It is important to evaluate risk of bias of the primary studies included in systematic reviews and meta-analyses. Since tools pertinent to surveys are scarce, the goal of the current research was to develop a measure to address this need. In Study 1, an initial list of 10 relevant topics was compiled from previous measures. In Study 2, the list was refined into an eight-item risk-of-bias measure via discussion and a pilot study. In Study 3, experienced researchers used the measure to asses 70 studies, demonstrating high interrater agreement (weighted Kappa = .82). Inexperienced raters also utilized the measure to code 26 different studies included in a prior meta-analysis, which resulted in adequate interrater agreement (weighted Kappa = .64) and excellent convergent validity (r = .66). Thus, the new measure, designed to be accessible and flexible, can increase standardization of risk-of-bias evaluations and contribute to the interpretation of systematic reviews and meta-analytic findings.

scholarly journals Processed Meat Consumption and the Risk of Cancer: A Critical Evaluation of the Constraints of Current Evidence from Epidemiological Studies

Nutrients ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 3601
Author(s):  
Mina Nicole Händel ◽  
Jeanett Friis Rohde ◽  
Ramune Jacobsen ◽  
Berit Lilienthal Heitmann
Keyword(s):  
General Population ◽  
Systematic Reviews ◽  
Methodological Quality ◽  
Meat Products ◽  
Meat Consumption ◽  
Risk Of Bias ◽  
Processed Meat ◽  
Meta Analyses ◽  
Risk Of Cancer ◽  
Processed Meat Consumption

Based on a large volume of observational scientific studies and many summary papers, a high consumption of meat and processed meat products has been suggested to have a harmful effect on human health. These results have led guideline panels worldwide to recommend to the general population a reduced consumption of processed meat and meat products, with the overarching aim of lowering disease risk, especially of cancer. We revisited and updated the evidence base, evaluating the methodological quality and the certainty of estimates in the published systematic reviews and meta-analyses that examined the association between processed meat consumption and the risk of cancer at different sites across the body, as well as the overall risk of cancer mortality. We further explored if discrepancies in study designs and risks of bias could explain the heterogeneity observed in meta-analyses. In summary, there are severe methodological limitations to the majority of the previously published systematic reviews and meta-analyses that examined the consumption of processed meat and the risk of cancer. Many lacked the proper assessment of the methodological quality of the primary studies they included, or the literature searches did not fulfill the methodological standards needed in order to be systematic and transparent. The primary studies included in the reviews had a potential risk for the misclassification of exposure, a serious risk of bias due to confounding, a moderate to serious risk of bias due to missing data, and/or a moderate to serious risk of selection of the reported results. All these factors may have potentially led to the overestimation of the risk related to processed meat intake across all cancer outcomes. Thus, with the aim of lowering the risk of cancer, the recommendation to reduce the consumption of processed meat and meat products in the general population seems to be based on evidence that is not methodologically strong.

Auriculoterapia para o tratamento da ansiedade em estudantes universitários: revisão sistemática

2021 ◽  
Author(s):  
◽  
Lara dos Santos Silva
Keyword(s):  
Clinical Trials ◽  
Systematic Reviews ◽  
Ad Hoc ◽  
Cochrane Collaboration ◽  
Risk Of Bias ◽  
Meta Analyses ◽  
Tecnología Educativa

A ansiedade está entre os transtornos mentais de maior prevalência na população mundial, sendo a segunda causa de incapacidade mental no mundo. Dentre a população suscetível à ansiedade, destacam-se os estudantes universitários, em decorrência das situações vivenciadas no âmbito acadêmico. Os tratamentos da ansiedade podem estar pautados em recursos medicamentosos e não medicamentosos. Dentre os não medicamentosos, destacam-se as Práticas Integrativas e Complementares em Saúde e, dentre estas, a auriculoterapia. O objetivo geral deste estudo foi s intetizar as evidências disponíveis na literatura científica sobre o uso da auriculoterapia no tratamento da ansiedade em estudantes universitários. Trata-se de uma revisão sistemática da literatura, realizada em 16 bases de dados, com início em 20 de janeiro e revisão até 27 de março de 2021. Todo o processo de busca e seleção dos artigos foi feito de modo independente e pareado, e, quando necessário, um terceiro pesquisador com experiência na temática auxiliava como ad hoc na resolução dos conflitos. O relato da revisão pautou-se na diretriz Preferred Reporting Items for Systematic Reviews and Meta-Analyses, e o protocolo da revisão foi cadastrado na plataforma International Prospective Register of Systematic Reviews (registro No CRD42020205968). Utilizou-se as diretrizes Standards for Reporting Interventions in Clinical Trials of Acupuncture, Cochrane Collaboration Risk of Bias Tool, e escala de JADAD para avaliação dos artigos. A amostra final foi composta por cinco artigos. A análise dos mesmos mostrou que a auriculoterapia contribuiu para tratar a ansiedade de estudantes universitários. O uso desta intervenção deve ser considerado pelas instituições formadoras para promoção da saúde mental nesta população, e pode contribuir para a melhora do desempenho acadêmico, redução das taxas de evasão, e melhora da qualidade de vida aos universitários. O estudo também possibilitou a elaboração de uma tecnologia educativa no formato de cartilha, com o objetivo de esclarecer aos estudantes universitários sobre a ansiedade como um problema de saúde relevante na população, bem como apresentar a auriculoterapia como uma possibilidade terapêutica. Pretende-se que, em momento oportuno, a mesma seja divulgada em formato eletrônico para toda a comunidade acadêmica. Palavras-chave: Auriculoterapia. Terapia auricular. Ansiedade. Estudantes.

What is the impact of physicians in prehospital treatment for patients in need of acute critical care? – An overview of reviews

2019 ◽  
Vol 35 (1) ◽  
pp. 27-35 ◽  
Author(s):  
Gitte Valentin ◽  
Lotte Groth Jensen
Keyword(s):  
Cardiac Arrest ◽  
Systematic Reviews ◽  
Critical Conditions ◽  
Current Evidence ◽  
Cochrane Library ◽  
Future Research ◽  
Success Rates ◽  
Prehospital Treatment ◽  
The Impact ◽  
Hospital Cardiac Arrest

AbstractObjectivesThe aim of this overview was to systematically identify and synthesize existing evidence from systematic reviews on the impact of prehospital physician involvement.MethodsThe Medline, Embase, and Cochrane library were searched from 1 January 2000 to 17 November 2017. We included systematic reviews comparing physician-based with non–physician-based prehospital treatment in patients with one of five critical conditions requiring a rapid response.ResultsTen reviews published from 2009 to 2017 were included. Physician treatment was associated with increased survival in patients with out-of-hospital cardiac arrest and patients with severe trauma; in the latter group, the result was based on more limited evidence. The success rate of prehospital endotracheal intubation (ETI) has improved over the years, but ETI by physicians is still associated with higher success rates than intubation by paramedics. In patients with severe traumatic brain injury, intubation by paramedics who were not well skilled to do so markedly increased mortality.ConclusionsCurrent evidence is hinting at a benefit of physicians in selected aspects of prehospital emergency services, including treatment of patients with out-of-hospital cardiac arrest and critically ill or injured patients in need of prehospital intubation. Evidence is, however, limited by confounding and bias, and comparison is hampered by differences in case mix and the organization of emergency medical services. Future research should strive to design studies that enable appropriate control of baseline confounding and obtain follow-up data for the proportion of patients who die in the prehospital setting.

scholarly journals Management of haemorrhoids: protocol of an umbrella review of systematic reviews and meta-analyses

BMJ Open ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. e035287
Author(s):  
Min Chen ◽  
Tai-Chun Tang ◽  
Tao-Hong He ◽  
Yong-Jun Du ◽  
Di Qin ◽  
...  
Keyword(s):  
Systematic Reviews ◽  
Meta Analysis ◽  
Random Effect Model ◽  
Current Evidence ◽  
Cochrane Library ◽  
Final Report ◽  
Umbrella Review ◽  
Effect Model ◽  
Meta Analyses ◽  
The Impact

IntroductionThe prevalence of haemorrhoidal diseases was high in general population, and many treatments are proposed for the management of haemorrhoids. The treatments include conservative and surgical interventions; the credibility and strength of current evidence of their effectiveness are not comprehensively evaluated. We aim to evaluate the credibility of systematic reviews and meta-analyses that assess the effectiveness of the treatments for haemorrhoidal diseases through an umbrella review.Methods and analysisWe will search Ovid Medline, Embase, Cochrane library and Web of Science from inception to March 2020 without any language restriction. We will include meta-analyses that examine the effectiveness of treatments in the management of haemorrhoids. Two reviewers will independently screen the titles and abstracts of retrieved articles, and they will extract data from the included meta-analyses. For each meta-analysis, we will estimate the effect size of a treatment through the random-effect model and the fixed-effect model, and we will evaluate between-study heterogeneity (Cochrane’s Q and I2statistics) and small-study effect (Egger’s test); we will also estimate the evidence of excess significance bias. Evidence of each treatment will be graded according to prespecified criteria. Methodological quality of each meta-analysis will be evaluated by using Assessment of Multiple Systematic Reviews 2. The corrected cover area method will be used to assess the impact of overlap in reviews on the findings of the umbrella review.Ethics and disseminationWe will present the results of the umbrella review at conferences and publish the final report in a peer-reviewed journal. The umbrella review does not require ethical approval.PROSPERO registration numberCRD42019140702.

Is grey literature essential for a better control of publication bias in psychiatry? An example from three meta-analyses of schizophrenia

2005 ◽  
Vol 20 (8) ◽  
pp. 550-553 ◽  
Author(s):  
José Luis R. Martin ◽  
Víctor Pérez ◽  
Montse Sacristán ◽  
Enric Álvarez
Keyword(s):  
Publication Bias ◽  
Systematic Reviews ◽  
Meta Analysis ◽  
Grey Literature ◽  
Risk Of Bias ◽  
Medical Databases ◽  
Study Results ◽  
Heterogeneous Nature ◽  
Meta Analyses ◽  
Literature Material

AbstractSystematic reviews in mental health have become useful tools for health professionals in view of the massive amount and heterogeneous nature of biomedical information available today. In order to determine the risk of bias in the studies evaluated and to avoid bias in generalizing conclusions from the reviews it is therefore important to use a very strict methodology in systematic reviews. One bias which may affect the generalization of results is publication bias, which is determined by the nature and direction of the study results. To control or minimize this type of bias, the authors of systematic reviews undertake comprehensive searches of medical databases and expand on the findings, often undertaking searches of grey literature (material which is not formally published). This paper attempts to show the consequences (and risk) of generalizing the implications of grey literature in the control of publication bias, as was proposed in a recent systematic work. By repeating the analyses for the same outcome from three different systematic reviews that included both published and grey literature our results showed that confusion between grey literature and publication bias may affect the results of a concrete meta-analysis.

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