scholarly journals Is the Simplicity of the Evidence Pyramid Actually Detrimental for Understanding Evidence?

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Annette O'Connor
Keyword(s):  
Cohort Studies ◽  
Real World ◽  
Disease Risk ◽  
Case Reports ◽  
Meta Analysis ◽  
Information Source ◽  
Case Series ◽  
Case Control ◽  
Current Evidence ◽  
Case Control Studies

The evidence pyramid for assessing the efficacy of interventions under real world conditions has been used in various forms for many years, and to a lesser extent the pyramid has been used for assessing evidence for disease risk factors. While acknowledging minor differences, many pyramids list the following information sources for interventions in decreasing order of “validity”: systematic review and meta-analysis of randomised control trials, randomised controlled trials, cohort studies, case control studies, case series and case reports. The evidence pyramid is often used as a teaching aid to help clinicians and students visualise the concept that all studies might not have equal evidentiary value when evaluating real world efficacy.The rationale for the hierarchy of the pyramid is partially based on the potential for bias in some designs and partially based on the external validity of the information source. Designs with greater potential for bias “on average” are placed lower on the pyramid. The greater risk of bias means a greater risk that effect size estimates from studies lower on the pyramid may be systematically incorrect (overestimated or underestimated). As such, the evidence pyramid makes very broad statements about the design “on average”. Of course, for any particular study or topic, the pyramid may not be correct. Regardless, the generalisations described in the evidence pyramid have over the years been considered useful and use of the tool continues likely because of its simplicity. However, the validity of most pyramids that we have seen (and used ourselves, and published ourselves) is predicated on two potentially false concepts. The first potentially false concept conveyed by most evidence pyramids, is that there is only one case-control design and it is of lesser evidentiary value than cohort studies. The second potentially false concept conveyed by evidence pyramids is that the terms cohort, case control, and case series can be used to “filter” out studies of lower evidentiary value.In this presentation Annette discusses the validity of the evidence pyramid on the interpretation of evidence from primary research. She proposes a new way to think about evidence from primary studies using the framework for classifying epidemiologic studies proposed by Pearce (2012) based on incident and prevalent cases. This would also result in a rethinking of the current evidence pyramid.

Types of trials

2017 ◽  
Author(s):  
Mark Harrison
Keyword(s):  
Emergency Medicine ◽  
Cohort Studies ◽  
Case Reports ◽  
Meta Analysis ◽  
Case Series ◽  
Case Control ◽  
Controlled Trials ◽  
Case Control Studies ◽  
Advantages And Disadvantages ◽  
Randomized Controlled

This chapter describes types of trials as applied to Emergency Medicine, and in particular the Primary FRCEM examination. The chapter outlines the key details and advantages and disadvantages of case reports, case series, cohort studies, case–control studies, randomized controlled trials, crossover trials, systematic reviews, and meta-analysis. This chapter is laid out exactly following the RCEM syllabus, to allow easy reference and consolidation of learning.

scholarly journals Neurology and neuropsychiatry of COVID-19: a systematic review and meta-analysis of the early literature reveals frequent CNS manifestations and key emerging narratives

2021 ◽  
pp. jnnp-2021-326405
Author(s):  
Jonathan P Rogers ◽  
Cameron J Watson ◽  
James Badenoch ◽  
Benjamin Cross ◽  
Matthew Butler ◽  
...  
Keyword(s):  
Systematic Review ◽  
Cohort Studies ◽  
Meta Analysis ◽  
Neuropsychiatric Symptoms ◽  
Case Series ◽  
Case Control ◽  
Case Control Studies ◽  
Cross Sectional ◽  
Early Literature ◽  
Cross Sectional Studies

There is accumulating evidence of the neurological and neuropsychiatric features of infection with SARS-CoV-2. In this systematic review and meta-analysis, we aimed to describe the characteristics of the early literature and estimate point prevalences for neurological and neuropsychiatric manifestations. We searched MEDLINE, Embase, PsycINFO and CINAHL up to 18 July 2020 for randomised controlled trials, cohort studies, case-control studies, cross-sectional studies and case series. Studies reporting prevalences of neurological or neuropsychiatric symptoms were synthesised into meta-analyses to estimate pooled prevalence. 13 292 records were screened by at least two authors to identify 215 included studies, of which there were 37 cohort studies, 15 case-control studies, 80 cross-sectional studies and 83 case series from 30 countries. 147 studies were included in the meta-analysis. The symptoms with the highest prevalence were anosmia (43.1% (95% CI 35.2% to 51.3%), n=15 975, 63 studies), weakness (40.0% (95% CI 27.9% to 53.5%), n=221, 3 studies), fatigue (37.8% (95% CI 31.6% to 44.4%), n=21 101, 67 studies), dysgeusia (37.2% (95% CI 29.8% to 45.3%), n=13 686, 52 studies), myalgia (25.1% (95% CI 19.8% to 31.3%), n=66 268, 76 studies), depression (23.0% (95% CI 11.8% to 40.2%), n=43 128, 10 studies), headache (20.7% (95% CI 16.1% to 26.1%), n=64 613, 84 studies), anxiety (15.9% (5.6% to 37.7%), n=42 566, 9 studies) and altered mental status (8.2% (95% CI 4.4% to 14.8%), n=49 326, 19 studies). Heterogeneity for most clinical manifestations was high. Neurological and neuropsychiatric symptoms of COVID-19 in the pandemic’s early phase are varied and common. The neurological and psychiatric academic communities should develop systems to facilitate high-quality methodologies, including more rapid examination of the longitudinal course of neuropsychiatric complications of newly emerging diseases and their relationship to neuroimaging and inflammatory biomarkers.

scholarly journals The neurology and neuropsychiatry of COVID-19: a systematic review and meta-analysis of the early literature reveals frequent CNS manifestations and key emerging narratives

2021 ◽  
Author(s):  
Jonathan P Rogers ◽  
Cameron Watson ◽  
James Badenoch ◽  
Benjamin Cross ◽  
Matthew Butler ◽  
...  
Keyword(s):  
Systematic Review ◽  
Cohort Studies ◽  
Meta Analysis ◽  
Neuropsychiatric Symptoms ◽  
Case Series ◽  
Case Control ◽  
Case Control Studies ◽  
Cross Sectional ◽  
Early Literature ◽  
Cross Sectional Studies

Objectives There is accumulating evidence of the neurological and neuropsychiatric features of infection with SARS-CoV-2. In this systematic review and meta-analysis, we aimed to describe the characteristics of the early literature and estimate point prevalences for neurological and neuropsychiatric manifestations. Methods We searched MEDLINE, Embase, PsycInfo and CINAHL up to 18 July 2020 for randomised controlled trials, cohort studies, case-control studies, cross-sectional studies and case series. Studies reporting prevalences of neurological or neuropsychiatric symptoms were synthesised into meta-analyses to estimate pooled prevalence. Results 13,292 records were screened by at least two authors to identify 215 included studies, of which there were 37 cohort studies, 15 case-control studies, 80 cross-sectional studies and 83 case series from 30 countries. 147 studies were included in the meta-analysis. The symptoms with the highest prevalence were anosmia (43.1% [35.2-51.3], n=15,975, 63 studies), weakness (40.0% [27.9-53.5], n=221, 3 studies), fatigue (37.8% [31.6-44.4], n=21,101, 67 studies), dysgeusia (37.2% [30.0-45.3], n=13,686, 52 studies), myalgia (25.1% [19.8-31.3], n=66.268, 76 studies), depression (23.0 % [11.8-40.2], n=43,128, 10 studies), headache (20.7% [95% CI 16.1-26.1], n=64,613, 84 studies), anxiety (15.9% [5.6-37.7], n=42,566, 9 studies) and altered mental status (8.2% [4.4-14.8], n=49,326, 19 studies). Heterogeneity for most clinical manifestations was high. Conclusions Neurological and neuropsychiatric symptoms of COVID-19 in the pandemic's early phase are varied and common. The neurological and psychiatric academic communities should develop systems to facilitate high-quality methodologies, including more rapid examination of the longitudinal course of neuropsychiatric complications of newly emerging diseases and their relationship to neuroimaging and inflammatory biomarkers.

Soy Consumption with Risk of Coronary Heart Disease and Stroke: A Meta-Analysis of Observational Studies

2016 ◽  
Vol 46 (4) ◽  
pp. 242-252 ◽  
Author(s):  
Danfei Lou ◽  
Yuehua Li ◽  
Guoliang Yan ◽  
Jianhong Bu ◽  
Haihui Wang
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Cohort Studies ◽  
Observational Studies ◽  
Meta Analysis ◽  
Case Control ◽  
Inverse Association ◽  
Case Control Studies ◽  
Relative Risks ◽  
Product Consumption

Background: The association of soy product consumption with the relative risk of cardiovascular disease remains controversial. This meta-analysis aimed at investigating whether an association exists between soy consumption and the risk of stroke and coronary heart disease (CHD) in observational studies. Methods: A systematic search of the PubMed and EMBASE databases was performed for case-control and cohort studies that assessed soy consumption and the risk of stroke and CHD. Summary relative risks (SRRs) and 95% CIs were combined by using a random-effects model. Results: Of a total of 1,266 abstracts, 5 prospective cohort and 6 case-control studies met our inclusion criteria, and comprised 4,954 stroke and 7,616 CHD events. Based on the high vs. low analyses, combining cohort studies showed no association between soy intake and risk of stroke (SRR 0.92; 95% CI 0.70-1.10; Pheterogeneity = 0.236; I2 = 29.4%) or CHD (SRR 0.97; 95% CI 0.74-1.27; Pheterogeneity = 0.020; I2 = 62.7%), although a significantly inverse association between soy intake and the risk of stroke (SRR 0.54; 95% CI 0.34-0.87; Pheterogeneity = 0.001; I2 = 79.3%) and CHD (SRR 0.66; 95% CI 0.56-0.77; Pheterogeneity = 0.421; I2 = 0) was observed in case-control studies. No association between soy isoflavone intake and the risk of stroke and CHD was identified. Conclusion: There was limited evidence to indicate that soy consumption was inversely associated with the risk of stroke and CHD, although further studies, with prospective designs that use validated questionnaires and control for important confounders, are warranted.

scholarly journals Dietary patterns and CVD: a systematic review and meta-analysis of observational studies

2015 ◽  
Vol 114 (9) ◽  
pp. 1341-1359 ◽  
Author(s):  
Míriam Rodríguez-Monforte ◽  
Gemma Flores-Mateo ◽  
Emília Sánchez
Keyword(s):  
Cohort Studies ◽  
Dietary Patterns ◽  
Observational Studies ◽  
Protective Factor ◽  
Meta Analysis ◽  
Epidemiological Studies ◽  
Case Control ◽  
Case Control Studies ◽  
Chd Risk ◽  
Control Comparison

AbstractEpidemiological studies show that diet is linked to the risk of developing CVD. The objective of this meta-analysis was to estimate the association between empirically derived dietary patterns and CVD. PubMed was searched for observational studies of data-driven dietary patterns that reported outcomes of cardiovascular events. The association between dietary patterns and CVD was estimated using a random-effects meta-analysis with 95 % CI. Totally, twenty-two observational studies met the inclusion criteria. The pooled relative risk (RR) for CVD, CHD and stroke in a comparison of the highest to the lowest category of prudent/healthy dietary patterns in cohort studies was 0·69 (95 % CI 0·60, 0·78; I2=0 %), 0·83 (95 % CI 0·75, 0·92; I2=44·6 %) and 0·86 (95 % CI 0·74, 1·01; I2=59·5 %), respectively. The pooled RR of CHD in a case–control comparison of the highest to the lowest category of prudent/healthy dietary patterns was 0·71 (95 % CI 0·63, 0·80; I2=0 %). The pooled RR for CVD, CHD and stroke in a comparison of the highest to the lowest category of western dietary patterns in cohort studies was 1·14 (95 % CI 0·92, 1·42; I2=56·9 %), 1·03 (95 % CI 0·90, 1·17; I2=59·4 %) and 1·05 (95 % CI 0·91, 1·22; I2=27·6 %), respectively; in case–control studies, there was evidence of increased CHD risk. Our results support the evidence of the prudent/healthy pattern as a protective factor for CVD.

scholarly journals Association of Helicobacter pylori Infection with the Risk of Metabolic Syndrome and Insulin Resistance: An Updated Systematic Review and Meta-Analysis

2021 ◽  
Author(s):  
Mobin Azami ◽  
Hamid Reza Baradaran ◽  
Parisa Kohnepoushi ◽  
Lotfolah Saed ◽  
Asra Moradkhani ◽  
...  
Keyword(s):  
Systematic Review ◽  
Insulin Resistance ◽  
Metabolic Syndrome ◽  
Helicobacter Pylori ◽  
Cohort Studies ◽  
Odds Ratio ◽  
Meta Analysis ◽  
Case Control ◽  
Case Control Studies ◽  
H Pylori

Abstract Background Conflicting results of recent studies on the association between Helicobacter pylori (H. pylori) infection and the risk of insulin resistance and metabolic syndrome explored the need for updated meta-analysis on this issue. Therefore, this systematic review aimed to estimate the pooled effect of H. pylori infection on the risk of insulin resistance and metabolic syndrome. Methods To identify case-control studies and cohort studies evaluating the association of H. pylori infection with insulin resistance and metabolic syndrome, a comprehensive literature search was performed from international databases including Medline (PubMed), Web of Sciences, Scopus, EMBASE, and CINHAL from January 1990 until January 2021. We used odds ratio with its 95% confidence interval (95%CI) to quantify the effect of case-control studies and risk ratio with its 95%CI for the effect of cohort studies. Results 22 studies with 206911 participants were included for meta-analysis. The pooled estimate of odds ratio between H. pylori infection and metabolic syndrome in case-control studies was 1.19 (95%CI: 1.05, 1.35; I2 = 0%), and in cohort studies, the pooled risk ratio was 1.31 (95%CI: 1.13, 1.51; I2 = 0%). Besides, case-control studies showed the pooled odds ratio of 1.54 (95%CI: 1.19, 1.98; I2 = 6.88%) for the association between H. pylori infection and insulin resistance. Conclusion A positive association was found between H. pylori infection and insulin resistance as well as metabolic syndrome, so planning to eliminate or eradicate H. pylori infection could be an effective solution to improve metabolic syndrome or insulin resistance, and vice versa.

Abstract 12672: Post-Implantation Hematoma Increases Risk of Cardiac Implantable Electronic Device Infection: A Systematic Review and Meta-analysis

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Jakrin Kewcharoen ◽  
Chanavuth Kanitsoraphan ◽  
Sittinun Thangjui ◽  
Thiratest Leesutipornchai ◽  
Leenhapong Navaravong
Keyword(s):  
Systematic Review ◽  
Cohort Studies ◽  
Electronic Device ◽  
Meta Analysis ◽  
Case Control ◽  
Cardiac Implantable Electronic Device ◽  
Case Control Studies ◽  
Randomized Controlled ◽  
Device Infection ◽  
Post Implantation

Introduction: Several studies have shown inconsistent relationship between post-implantation hematoma (PH) and cardiac implantable electronic device (CIED) infection. In this study, we performed a systematic review and meta-analysis to explore the effect of PH and the risk of CIED infection. Hypothesis: PH increases the risk of CIED infection. Methods: We searched the databases of MEDLINE and EMBASE from inception to March 2020. Included studies were cohort studies, case-control studies, cross-sectional studies and randomized controlled trials that reported incidence of PH and CIED infection during the follow-up period. CIED infection was defined as either a device-related local or systemic infection. Data from each study were combined using the random-effects, generic inverse variance method of Der Simonian and Laird to calculate odds ratios (OR) and 95% confidence intervals (CI). Results: Fourteen studies from 2006 to 2018 were included, involving a total of 28,319 participants. There were 6 cohort studies, 7 case-control studies and 1 randomized controlled trial. In random-effect model, we found that PH significantly increases the risk of overall CIED infection (OR = 6.30, 95%CI: 3.87-10.24, I2=49.3%) (Figure 1). There was no publication bias observed in the funnel plot as well as no small-study effect observed in Egger’s test. Conclusions: Our meta-analysis demonstrated that PH significantly increases the risk of CIED infection. Precaution should be taken to during device implantation to reduce PH and subsequent CIED infection.

Are Clinical Outcomes Associated With Medication Regimen Complexity? A Systematic Review and Meta-analysis

2019 ◽  
Vol 54 (4) ◽  
pp. 301-313 ◽  
Author(s):  
Vanessa Alves-Conceição ◽  
Kérilin Stancine Santos Rocha ◽  
Fernanda Vilanova Nascimento Silva ◽  
Rafaella de Oliveira Santos Silva ◽  
Sabrina Cerqueira-Santos ◽  
...  
Keyword(s):  
Systematic Review ◽  
Cohort Studies ◽  
Clinical Outcomes ◽  
Meta Analysis ◽  
Case Control ◽  
Current Evidence ◽  
Medication Regimen ◽  
Medication Regimen Complexity ◽  
Complexity Index ◽  
Regimen Complexity

Background: Current evidence of the influence of the medication regimen complexity (MRC) on the patients’ clinical outcomes are not conclusive. Objective: To systematically and analytically assess the association between MRC measured by the Medication Regimen Complexity Index (MRCI) and clinical outcomes. Methods: A search was carried out in the databases Cochrane Library, LILACS, PubMed, Scopus, EMBASE, Open Thesis, and Web of Science to identify studies evaluating the association between MRC and clinical outcomes that were published from January 1, 2004, to April 2, 2018. The search terms included outcome assessment, drug therapy, and medication regimen complexity index and their synonyms in different combinations for case-control and cohort studies that used the MRCI to measure MRC and related the MRCI with clinical outcomes. Odds ratios (ORs), hazard ratios (HRs), and mean differences (WMDs) were calculated, and heterogeneity was assessed using the I2 test. Results: A total of 12 studies met the eligibility criteria. The meta-analysis showed that MRC is associated with the following clinical outcomes: hospitalization (HR = 1.20; 95% CI = 1.14 to 1.27; I2 = 0%) in cohort studies, hospital readmissions (WMD = 7.72; 95% CI = 1.19 to 14.25; I2 = 84%) in case-control studies, and medication nonadherence (adjusted OR = 1.05; 95% CI = 1.02 to 1.07; I2 = 0%) in cohort studies. Conclusion and Relevance: This systematic review and meta-analysis gathered relevant scientific evidence and quantified the combined estimates to show the association of MRC with clinical outcomes: hospitalization, hospital readmission, and medication adherence.

scholarly journals Usefulness of surgical treatment for asymptomatic patients with extra-peritoneal desmoid-type fibromatosis: a systematic review and meta-analysis

2020 ◽  
Vol 50 (5) ◽  
pp. 574-580
Author(s):  
Munehisa Kito ◽  
Akira Ogose ◽  
Masahiro Yoshida ◽  
Yoshihiro Nishida
Keyword(s):  
Surgical Treatment ◽  
Treatment Group ◽  
Progressive Disease ◽  
Meta Analysis ◽  
Case Series ◽  
Case Control ◽  
Case Control Studies ◽  
Exacerbation Rate ◽  
Asymptomatic Patients ◽  
Non Surgical Treatment

Abstract Objective The purpose of this systematic review is to assess and compare the efficacy of surgical treatment for patients with asymptomatic extra-peritoneal desmoid-type fibromatosis to the wait-and-see policy by evaluating (1) the exacerbation rate (exacerbation; recurrence after surgery or progressive disease following non-surgical treatment) and (2) treatment-associated complications in extra-peritoneal desmoid-type fibromatosis. Methods We evaluated documents published between 1 January 1990 and 31 August 2017. The risk of bias in the selected literature was analyzed using the Cochrane Collaboration Risk of Bias Tool. Quality of evidence was evaluated using Grading of Recommendation, Assessment, Development and Evaluation approach. Results One prospective cohort study, four case–control studies and five case series studies were identified. Meta-analysis was performed to evaluate the exacerbation rate after treatment on one prospective cohort study and four case–control studies. In comparing surgical and non-surgical treatments, the exacerbation rate was significantly higher in the surgical treatment group (odds ratio: 1.32, 95% confidence interval 1.01–1.73, P = 0.05). However, in the case series study, the recurrence rate was 23.4% for the surgical treatment group, while the progressive disease rate was 28.1% for the non-surgical treatment group. The postoperative complication rates associated with surgical treatment in the two studies were 20.8 and 17.2%, respectively. Conclusions When considering the exacerbation rate, non-surgical treatment might be appropriate for asymptomatic patients with extra-peritoneal desmoid-type fibromatosis. However, if patients with tumor-related symptoms opt for surgery, including those who face difficulties due to the presence of tumors, it is important to fully explain to them the possibility that the recurrence rate and treatment-associated functional failures may increase depending on the site of occurrence.

Sign in / Sign up

Export Citation Format

Share Document