Measuring statistical heterogeneity: The Pietra index

2010 ◽  
Vol 389 (1) ◽  
pp. 117-125 ◽  
Author(s):  
Iddo I. Eliazar ◽  
Igor M. Sokolov
Keyword(s):  
Statistical Heterogeneity ◽  
Pietra Index

Effects of diacerein intake on cardiometabolic profiles in type 2 diabetics: a systematic review and meta-analysis of clinical trials.

2020 ◽  
Vol 27 ◽  
Author(s):  
Peyman Nowrouzi-Sohrabi ◽  
Reza Tabrizi ◽  
Mohammad Jalali ◽  
Navid Jamali ◽  
Shahla Rezaei ◽  
...  
Keyword(s):  
Systematic Review ◽  
Clinical Trials ◽  
Body Weight ◽  
Total Cholesterol ◽  
Ldl Cholesterol ◽  
Meta Analysis ◽  
Hdl Cholesterol ◽  
Cochrane Central Register ◽  
Statistical Heterogeneity

Introduction: A systematic review and meta-analysis of clinical trials was undertaken to evaluate the effect of diacerein intake on cardiometabolic profiles in patients with type 2 diabetes mellitus (T2DM). Methods: Electronic databases such as PubMed, EMBASE, Scopus, Web of Science, Google Scholar, and Cochrane Central Register of Controlled Trials were searched from inception to 31 July 2019. Statistical heterogeneity was evaluated using Cochran’s Q test and I-square (I2 ) statistic. Data were pooled using random-effect models and weighted mean difference (WMD). Results: From 1,733 citations, seven clinical trials were eligible for inclusion and meta-analysis. A significant reduction in hemoglobin A1c (HbA1c) (WMD -0.73; 95%CI -1.25 to -0.21; P= 0.006; I2 = 72.2%) and body mass index (BMI) (WMD -0.55; 95%CI -1.03 to -0.07; P= 0.026; I2 = 9.5%) were identified. However, no significant effect of diacerein intake was identified on fasting blood sugar (FBS) (WMD - 9.00; 95%CI -22.57 to 4.57; P= 0.194; I2 = 60.5%), homeostatic model assessment for insulin resistance (HOMA-IR) (WMD 0.39; 95%CI 0.95 to 1.73; P= 0.569; I2 = 2.2%), body weight (WMD -0.54; 95%CI -1.10 to 0.02; P= 0.059), triglycerides (WMD -0.56; 95%CI -24.16 to 23.03; P= 0.963; I2 = 0.0%), total-cholesterol (WMD -0.21; 95%CI -12.19 to 11.78; P= 0.973; I2 = 0.0%), HDL-cholesterol (WMD -0.96; 95%CI -2.85 to 0.93; P= 0.321; I2 = 0.0%), and LDL-cholesterol levels (WMD -0.09; 95%CI -8.43 to 8.25; P= 0.983; I2 = 37.8%). Conclusion: Diacerein intake may reduce HbA1c and BMI; however, no evidence of effect was observed for FBS, HOMA-IR, body weight, triglycerides, total-cholesterol, HDL-cholesterol or LDL-cholesterol.

scholarly journals Dyslipidaemia and mortality in COVID-19 patients - a meta-analysis

QJM ◽  
2021 ◽  
Author(s):  
Marco Zuin ◽  
Gianluca Rigatelli ◽  
Claudio Bilato ◽  
Carlo Cervellati ◽  
Giovanni Zuliani ◽  
...  
Keyword(s):  
Random Effects ◽  
Mortality Risk ◽  
Meta Analysis ◽  
Random Effect ◽  
Final Analysis ◽  
Short Term ◽  
Random Effects Models ◽  
Pooled Prevalence ◽  
Statistical Heterogeneity ◽  
Trim And Fill

Abstract Objective The prevalence and prognostic implications of pre-existing dyslipidaemia in patients infected by the SARS-CoV-2 remain unclear. To perform a systematic review and meta-analysis of prevalence and mortality risk in COVID-19 patients with pre-existing dyslipidaemia. Methods Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed in abstracting data and assessing validity. We searched MEDLINE and Scopus to locate all the articles published up to January 31, 2021, reporting data on dyslipidaemia among COVID-19 survivors and non-survivors. The pooled prevalence of dyslipidaemia was calculated using a random effects model and presenting the related 95% confidence interval (CI), while the mortality risk was estimated using the Mantel-Haenszel random effects models with odds ratio (OR) and related 95% CI. Statistical heterogeneity was measured using the Higgins I2 statistic. Results Eighteen studies, enrolling 74.132 COVID-19 patients [mean age 70.6 years], met the inclusion criteria and were included in the final analysis. The pooled prevalence of dyslipidaemia was 17.5% of cases (95% CI: 12.3-24.3%, p < 0.0001), with high heterogeneity (I2=98.7%). Pre-existing dyslipidaemia was significantly associated with higher risk of short-term death (OR: 1.69, 95% CI: 1.19-2.41, p = 0.003), with high heterogeneity (I2=88.7%). Due to publication bias, according to the Trim-and-Fill method, the corrected random-effect ORs resulted 1.61, 95% CI 1.13-2.28, p < 0.0001 (one studies trimmed). Conclusions Dyslipidaemia represents a major comorbidity in about 18% of COVID-19 patients but it is associated with a 60% increase of short-term mortality risk.

scholarly journals Coenzyme Q10 supplementation for prophylaxis in adult patients with migraine—a meta-analysis

BMJ Open ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. e039358
Author(s):  
Suhairul Sazali ◽  
Salziyan Badrin ◽  
Mohd Noor Norhayati ◽  
Nur Suhaila Idris
Keyword(s):  
Random Effects ◽  
Coenzyme Q10 ◽  
Migraine Headache ◽  
Meta Analysis ◽  
Adult Patients ◽  
Control Group ◽  
Cochrane Central Register ◽  
Statistical Heterogeneity ◽  
Coq10 Supplementation ◽  
The Impact

ObjectiveTo determine the effects of coenzyme Q10 (CoQ10) for reduction in the severity, frequency of migraine attacks and duration of headache in adult patients with migraine.DesignSystematic review and meta-analysis.Data sourcesCochrane Central Register of Controlled Trials, CENTRAL, MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Psychological Information Database (PsycINFO) from inception till December 2019.Study selectionAll randomised control trials comparing CoQ10 with placebo or used as an adjunct treatment included in this meta-analysis. Cross-over designs and controlled clinical trials were excluded.Data synthesisHeterogeneity at face value by comparing populations, settings, interventions and outcomes were measured and statistical heterogeneity was assessed by means of the I2 statistic. The treatment effect for dichotomous outcomes were using risk ratios and risk difference, and for continuous outcomes, mean differences (MDs) or standardised mean difference; both with 95% CIs were used. Subgroup analyses were carried out for dosage of CoQ10 and if CoQ10 combined with another supplementation. Sensitivity analysis was used to investigate the impact risk of bias for sequence generation and allocation concealment of included studies.ResultsSix studies with a total of 371 participants were included in the meta-analysis. There is no statistically significant reduction in severity of migraine headache with CoQ10 supplementation. CoQ10 supplementation reduced the duration of headache attacks compared with the control group (MD: −0.19; 95% CI: −0.27 to −0.11; random effects; I2 statistic=0%; p<0.00001). CoQ10 usage reduced the frequency of migraine headache compared with the control group (MD: −1.52; 95% CI: −2.40 to −0.65; random effects; I2 statistic=0%; p<0.001).ConclusionCoQ10 appears to have beneficial effects in reducing duration and frequency of migraine attack.PROSPERO registration numberCRD42019126127.

scholarly journals Greater cardiorespiratory fitness reduces incidence of atrial fibrillation: a meta-analysis

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
C Verdicchio ◽  
A Elliott ◽  
R Mahajan ◽  
D Linz ◽  
D Lau ◽  
...  
Keyword(s):  
Risk Factors ◽  
Atrial Fibrillation ◽  
Risk Factor ◽  
Cardiorespiratory Fitness ◽  
Meta Analysis ◽  
Exercise Stress ◽  
Inverse Association ◽  
Exercise Interventions ◽  
Increased Risk ◽  
Statistical Heterogeneity

Abstract Funding Acknowledgements Type of funding sources: None. Introduction  Atrial Fibrillation (AF) is the most common sustained cardiac arrhythmia affecting 1-2% of the global population, with the prevalence of AF increasing dramatically over the past two decades. Although low levels of cardiorespiratory fitness (CRF) and physical activity are predictive of cardiovascular disease onset and mortality, only recently has this emerged as a potential risk factor for AF. Purpose The aim of this meta-analysis was therefore to quantify the relationship between CRF, measured by a symptom limited exercise stress test, and incident AF. We hypothesised that there would be an inverse relationship between CRF and the incidence of AF. Methods The systematic literature review was conducted using PUBMED, MEDLINE and EMBASE databases, with seven studies meeting the inclusion criteria. A random-effects meta-analysis was then used to compare the multivariate risk estimates of the lowest CRF group from each cohort with the group of the highest CRF. Results Data from 206,925 individuals (55.8% males) was used for analysis with a mean age of 55 ± 2.5 years and a mean follow-up period of 10.3 ± 5 years. The total number of AF events across the studies was 19,913. The overall pooled risk of AF in the high-CRF group versus the low-CRF group showed a significant lower risk of incident AF in those with high-CRF (OR: 0.52, 95% CI, 0.44-0.605, p &lt; 0.001). There was evidence of statistical heterogeneity between the studies (I2 = 81%, p &lt; 0.001). AF incidence rates demonstrated an overall decline in rates across the CRF quartiles from low to high. The mean incidence rate for low-CRF was 21 ± 13.4 compared to 6.9 ± 0.7 per 1000 person-years for the high CRF group (p = 0.03). Conclusion There is an inverse association between a lower CRF and an increased risk of AF, with a higher level of CRF protective against AF. This study highlights that low-CRF may be an additional risk factor for AF along with already other established lifestyle-based risk factors such as obesity and hypertension. Exercise interventions should be promoted as a primary prevention strategy in those at risk of developing AF with known risk factors. Future studies are warranted to identify the mechanism(s) through which improved CRF confers a reduction in AF incidence. Abstract Figure. AF risk between high and low-CRF

scholarly journals Interventional radiology versus operative management for splenic injuries: a study protocol for a systematic review and meta-analysis

BMJ Open ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. e028172
Author(s):  
Masahiro Kashiura ◽  
Noritaka Yada ◽  
Kazuma Yamakawa
Keyword(s):  
Systematic Review ◽  
Interventional Radiology ◽  
Meta Analysis ◽  
Operative Management ◽  
Sensitivity Analyses ◽  
Definitive Treatment ◽  
Controlled Trials ◽  
Cochrane Central Register ◽  
Statistical Heterogeneity ◽  
Non Operative Management

IntroductionOver the past decades, the treatment for blunt splenic injuries has shifted from operative to non-operative management. Interventional radiology such as splenic arterial embolisation generally increases the success rate of non-operative management. However, the type of intervention, such as the first definitive treatment for haemostasis (interventional radiology or surgery) in blunt splenic injuries is unclear. Therefore, we aim to clarify whether interventional radiology improves mortality in patients with blunt splenic trauma compared with operative management by conducting a systematic review and meta-analysis.Methods and analysisWe will search the following electronic bibliographic databases to retrieve relevant articles for the literature review: Medline, Embase and the Cochrane Central Register of Controlled Trials. We will include controlled trials and observational studies published until September 2018. We will screen search results, assess the study population, extract data and assess the risk of bias. Two review authors will extract data independently, and discrepancies will be identified and resolved through a discussion with a third author where necessary. Data from eligible studies will be pooled using a random-effects meta-analysis. Statistical heterogeneity will be assessed by using the Mantel-Haenszel χ² test and the I² statistic, and any observed heterogeneity will be quantified using the I² statistic. We will conduct sensitivity analyses according to several factors relevant for the heterogeneity.Ethics and disseminationOur study does not require ethical approval as it is based on the findings of previously published articles. This systematic review will provide guidance on selecting a method for haemostasis of splenic injuries and may also identify knowledge gaps that could direct further research in the field. Results will be disseminated through publication in a peer-reviewed journal and presentations at relevant conferences.PROSPERO registration numberCRD42018108304.

scholarly journals Magnesium Metabolism in Chronic Alcohol-Use Disorder: Meta-Analysis and Systematic Review

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1959
Author(s):  
Flora O. Vanoni ◽  
Gregorio P. Milani ◽  
Carlo Agostoni ◽  
Giorgio Treglia ◽  
Pietro B. Faré ◽  
...  
Keyword(s):  
Alcohol Use ◽  
Alcohol Use Disorder ◽  
Meta Analysis ◽  
Final Analysis ◽  
Magnesium Content ◽  
Chronic Alcohol ◽  
Renal Handling ◽  
Intracellular Magnesium ◽  
Magnesium Depletion ◽  
Statistical Heterogeneity

Chronic alcohol-use disorder has been imputed as a possible cause of dietary magnesium depletion. The purpose of this study was to assess the prevalence of hypomagnesemia in chronic alcohol-use disorder, and to provide information on intracellular magnesium and on its renal handling. We carried out a structured literature search up to November 2020, which returned 2719 potentially relevant records. After excluding non-significant records, 25 were retained for the final analysis. The meta-analysis disclosed that both total and ionized circulating magnesium are markedly reduced in chronic alcohol-use disorder. The funnel plot and the Egger’s test did not disclose significant publication bias. The I2-test demonstrated significant statistical heterogeneity between studies. We also found that the skeletal muscle magnesium content is reduced and the kidney’s normal response to hypomagnesemia is blunted. In conclusion, magnesium depletion is common in chronic alcohol-use disorder. Furthermore, the kidney plays a crucial role in the development of magnesium depletion.

scholarly journals Platelet function and cardiovascular risk in adult HIV-infected patients on HAART: a protocol for a systematic review and meta-analysis

BMJ Open ◽  
2017 ◽  
Vol 7 (12) ◽  
pp. e019468 ◽  
Author(s):  
Bongani Brian Nkambule ◽  
Zibusiso Mkandla ◽  
Tinashe Mutize ◽  
Phiwayinkosi Vusi Dludla
Keyword(s):  
Risk Factors ◽  
Systematic Review ◽  
Cardiovascular Risk ◽  
Platelet Activation ◽  
Meta Analysis ◽  
People Living With Hiv ◽  
Qualitative Synthesis ◽  
Cvd Risk ◽  
Increased Risk ◽  
Statistical Heterogeneity

IntroductionThe incidence of cardiovascular disease (CVD) is now at least threefold higher in HIV-infected patients as compared with the general population. Although platelet activation and reactivity are implicated in the development of CVDs in HIV-infected patients, its precise role remains inconclusive. We aim to assess the association between platelet activation and selected cardiovascular risk factors in HIV-1-infected individuals on highly active antiretroviral treatment (HAART).MethodsThis will be a systematic review and meta-analysis of published studies evaluating the association between platelet activation and CVD risk factors in HAART-treated adults. The search strategy will include medical subject headings words for MEDLINE, and this will be adapted to Embase search headings (Emtree) terms for the EMBASE database. The search will cover literature published between 1 January 1996 to 30 April 2017. Studies will be independently screened by two reviewers using predefined criteria. Relevant eligible full texts will be screened; data will be extracted, and a qualitative synthesis will be conducted. Data extraction will be performed using Review Manager V.5.3. To assess the quality and strengths of evidence across selected studies, the Grading of Recommendations Assessment Development and Evaluation approach will be used. The Cochran’s Q statistic and the I2statistics will be used to analyse statistical heterogeneity between studies. If included studies show high levels of homogeneity, a random effects meta-analysis will be performed using R statistical software.Ethics and disseminationThis will be a review of existing studies and will not require ethical approval. The findings will be disseminated through peer-reviewed publication and presented at local and international conferences. An emerging patient management dilemma is that of the increased incidence of CVD in people living with HIV on HAART. This review may inform treatment and cardiovascular risk stratification of HIV-infected patients at increased risk of developing CVD.PROSPERO registration numberCRD42017062393.

scholarly journals Antimicrobial-impregnated and -coated shunt catheters for prevention of infections in patients with hydrocephalus: a systematic review and meta-analysis

2015 ◽  
Vol 122 (5) ◽  
pp. 1096-1112 ◽  
Author(s):  
Athanasios A. Konstantelias ◽  
Konstantinos Z. Vardakas ◽  
Konstantinos A. Polyzos ◽  
Giannoula S. Tansarli ◽  
Matthew E. Falagas
Keyword(s):  
De Novo ◽  
Meta Analysis ◽  
Ventricular Drainage ◽  
Gram Negative ◽  
Ventriculoperitoneal Shunting ◽  
Csf Shunting ◽  
Statistical Heterogeneity ◽  
Catheter Implantation ◽  
Prevention Of Infections ◽  
Definition Of

OBJECT The aim of this study was to evaluate the effectiveness of antimicrobial-impregnated and -coated shunt catheters (antimicrobial catheters) in reducing the risk of infection in patients undergoing CSF shunting or ventricular drainage. METHODS The PubMed and Scopus databases were searched. Catheter implantation was classified as either shunting (mainly ventriculoperitoneal shunting) or ventricular drainage (mainly external [EVD]). Studies evaluating antibioticimpregnated catheters (AICs), silver-coated catheters (SCCs), and hydrogel-coated catheters (HCCs) were included. A random effects model meta-analysis was performed. RESULTS Thirty-six studies (7 randomized and 29 nonrandomized, 16,796 procedures) were included. The majority of data derive from studies on the effectiveness of AICs, followed by studies on the effectiveness of SCCs. Statistical heterogeneity was observed in several analyses. Antimicrobial shunt catheters (AICs, SCCs) were associated with lower risk for CSF catheter–associated infections than conventional catheters (CCs) (RR 0.44, 95% CI 0.35–0.56). Fewer infections developed in the patients treated with antimicrobial catheters regardless of randomization, number of participating centers, funding, shunting or ventricular drainage, definition of infections, de novo implantation, and rate of infections in the study. There was no difference regarding gram-positive bacteria, all staphylococci, coagulase-negative streptococci, and Staphylococcus aureus, when analyzed separately. On the contrary, the risk for methicillin-resistant S. aureus (MRSA, RR 2.64, 95% CI 1.26–5.51), nonstaphylococcal (RR 1.75, 95% CI 1.22–2.52), and gram-negative bacterial (RR 2.13, 95% CI 1.33–3.43) infections increased with antimicrobial shunt catheters. CONCLUSIONS Based on data mainly from nonrandomized studies, AICs and SCCs reduce the risk for infection in patients undergoing CSF shunting. Future studies should evaluate the higher risk for MRSA and gram-negative infections. Additional trials are needed to investigate the comparative effectiveness of the different types of antimicrobial catheters.

Sentinel Lymph Node Molecular Ultrastaging in Patients With Melanoma: A Systematic Review and Meta-Analysis of Prognosis

2007 ◽  
Vol 25 (12) ◽  
pp. 1588-1595 ◽  
Author(s):  
Simone Mocellin ◽  
Dave S.B. Hoon ◽  
Pierluigi Pilati ◽  
Carlo R. Rossi ◽  
Donato Nitti
Keyword(s):  
Meta Analysis ◽  
Clinical Stage ◽  
Prognostic Indicator ◽  
Hematologic Malignancies ◽  
Disease Recurrence ◽  
Tnm Stage ◽  
Stage I ◽  
Clinical Implementation ◽  
Recurrence Rates ◽  
Statistical Heterogeneity

Purpose Molecular biology-based ultrastaging of cancer is already part of the standard management of patients with hematologic malignancies, whereas the evidence for solid tumors is much more debated. Polymerase chain reaction (PCR) –based detection of melanoma cells in sentinel lymph nodes (SLN) of patients with melanoma represents an appealing prognostic tool. However, no consensus exists on the clinical implementation of this prognostic indicator for the management of these patients. Methods Twenty-two studies enrolling 4,019 patients who underwent SLN biopsy for clinical stage I to II cutaneous melanoma were reviewed. Correlation of PCR status with TNM stage, disease recurrence rates, and survival was assessed by means of association statistics and formal meta-analysis, respectively. Results PCR status correlated with both TNM stage (stage I to II v III; PCR positivity, 95.1% v 46.6%; P < .0001) and disease recurrence (PCR positive v negative; relapse rate, 16.8% v 8.7%; P < .0001). PCR positivity was also associated with worse overall (hazard ratio [HR], 5.08; 95% CI, 1.83 to 14.08; P = .002) and disease-free (HR, 3.41; 95% CI, 1.86 to 6.24; P < .0001) survival. Statistical heterogeneity was significant, underscoring the variability among overall effect estimates across studies; metaregression and subgroup analysis did not identify clear-cut sources of heterogeneity, although some study design variables were suggested as potential causes. Conclusion PCR status of SLN appears to have a clinically valuable prognostic power in patients with melanoma. Although the heterogeneity of the studies so far published warrants caution to avoid overestimating the favorable results of pooled data, our findings strongly support additional investigation in this field.

Pharmacological Treatment of Osteoporosis in Elderly People: A Systematic Review and Meta-Analysis

Gerontology ◽  
2021 ◽  
pp. 1-11
Author(s):  
Qin-Yi Wang ◽  
Na Ding ◽  
Yi-He Dong ◽  
Zhang-Xin Wen ◽  
Rong Chen ◽  
...  
Keyword(s):  
Adverse Events ◽  
Elderly Patients ◽  
Meta Analysis ◽  
Controlled Trials ◽  
Cochrane Central Register ◽  
Anabolic Agents ◽  
Double Blind ◽  
Antiresorptive Agents ◽  
Statistical Heterogeneity ◽  
Post Hoc

<b><i>Background:</i></b> The evidence supporting the use of antiresorptive and anabolic agents for fracture prevention in elderly patients is still inconclusive. Whether it is too late to alter the course of the disease in this age-group has remained uncertain. <b><i>Objectives:</i></b> The objective of this study was to determine the efficacy and safety of antiresorptive and anabolic agents in elderly patients. <b><i>Methods:</i></b> PubMed, Web of Science, MEDLINE, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) and post hoc analyses of RCTs reporting efficacy outcomes or adverse events of antiresorptive and anabolic agents in elderly patients. Statistical heterogeneity was assessed with the Cochran <i>Q</i> χ<sup>2</sup> test and <i>I</i><sup>2</sup> statistic. All results were expressed as relative risk (RR) with 95% confidence intervals (CIs). <b><i>Results:</i></b> The meta-analysis included 1 RCT and 11 post hoc analyses of data from 10 double-blind placebo-controlled RCTs. Antiresorptive therapy significantly reduced the pooled incidence of vertebral fractures (RR = 0.43; 95% CI = 0.35–0.53; and <i>p</i> &#x3c; 0.001). It was also associated with lower risk of nonvertebral and hip fractures (RR = 0.84; 95% CI = 0.74–0.96; and <i>p</i> = 0.009 and RR = 0.75; 95% CI = 0.58–0.97; and <i>p</i> = 0.028, respectively). For any adverse events, no difference was observed between antiresorptive agents and placebo groups (RR = 1.01; 95% CI = 1.00–1.02; and <i>p</i> = 0.23). <b><i>Conclusions:</i></b> Both antiresorptive and anabolic agents represented potentially important osteoporosis treatments, showing significant effects on reducing vertebral, nonvertebral, or hip fracture risk, and were well-tolerated by elderly patients. Even in the elderly, maybe it is not too late to alter the course of the disease.

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