Quantifying uncertainty in method of moments estimates of the heterogeneity variance in random effects meta‐analysis

2021 ◽  
Author(s):  
Kurex Sidik ◽  
Jeffrey N. Jonkman
QJM ◽  
2021 ◽  
Author(s):  
Marco Zuin ◽  
Gianluca Rigatelli ◽  
Claudio Bilato ◽  
Carlo Cervellati ◽  
Giovanni Zuliani ◽  
...  

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.


2021 ◽  
Vol 10 (11) ◽  
pp. 2300
Author(s):  
Han-Chang Ku ◽  
Yi-Tseng Tsai ◽  
Sriyani-Padmalatha Konara-Mudiyanselage ◽  
Yi-Lin Wu ◽  
Tsung Yu ◽  
...  

The incidence of herpes zoster (HZ) in patients infected with HIV is higher than that of the general population. However, the incidence of HZ in HIV patients receiving antiretroviral therapy (ART) remains unclear. This meta-analysis aimed to estimate the pooled incidence rate and risk factors for HZ in the post-ART era. We identified studies assessing the incidence of HZ in the post-ART era between 1 January 2000 and 28 February 2021, from four databases. Pooled risk ratios were calculated from 11 articles using a random-effects model. The heterogeneity of the included trials was evaluated by visually inspecting funnel plots, performing random-effects meta-regression and using I2 statistics. Of the 2111 studies screened, we identified 11 studies that were eligible for final inclusion in the systematic review and 8 studies that were eligible for a meta-analysis. The pooled incidence of HZ in the post-ART era (after the introduction of ART in 1997) was 2.30 (95% confidence interval (CI): 1.56–3.05) per 100 person years (PYs). The risks of incidence of HZ among people living with HIV included male sex (AOR: 4.35 (95% CI: 054–2.41)), men who have sex with men (AOR: 1.21 (95% CI: −0.76–1.13)), CD4 count < 200 cells/μL (AOR: 11.59 (95% CI: 0.53–4.38)) and not receiving ART (AOR: 2.89 (95% CI: −0.44–2.56)). The incidence of HZ is substantially lower among HIV infected patients receiving ART than those not receiving ART. Initiating ART immediately after diagnosis to treat all HIV-positive individuals is crucial to minimize the disease burden of HZ.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Hui Meng ◽  
Yunping Zhou ◽  
Yunxia Jiang

AbstractObjectivesThe results of existing studies on bisphenol A (BPA) and puberty timing did not reach a consensus. Thereby we performed this meta-analytic study to explore the association between BPA exposure in urine and puberty timing.MethodsMeta-analysis of the pooled odds ratios (OR), prevalence ratios (PR) or hazards ratios (HR) with 95% confidence intervals (CI) were calculated and estimated using fixed-effects or random-effects models based on between-study heterogeneity.ResultsA total of 10 studies involving 5621 subjects were finally included. The meta-analysis showed that BPA exposure was weakly associated with thelarche (PR: 0.96, 95% CI: 0.93–0.99), while no association was found between BPA exposure and menarche (HR: 0.99, 95% CI: 0.89–1.12; OR: 1.02, 95% CI: 0.73–1.43), and pubarche (OR: 1.00, 95% CI: 0.79–1.26; PR: 1.00, 95% CI: 0.95–1.05).ConclusionsThere was no strong correlation between BPA exposure and puberty timing. Further studies with large sample sizes are needed to verify the relationship between BPA and puberty timing.


BMJ Open ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. e039358
Author(s):  
Suhairul Sazali ◽  
Salziyan Badrin ◽  
Mohd Noor Norhayati ◽  
Nur Suhaila Idris

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.


2021 ◽  
pp. 174749302110048
Author(s):  
Frederick Ewbank ◽  
Jacqueline Birks ◽  
Diederik Bulters

Abstract Background Some studies have shown a protective association between aspirin use and subarachnoid haemorrhage (SAH). Other studies have found no relationship or the reverse. These studies differ in their study populations and definitions of SAH. Aims Our aim was to establish 1) if there is an association between aspirin and SAH, 2) how this differs between the general population and those with intracranial aneurysms. Summary of review Studies reporting aspirin use and the occurrence of SAH were included and grouped based on population (general population vs aneurysm population). Odds ratios, hazard ratios and confidence intervals were combined in random-effects models. 11 studies were included. Overall, there was an association between aspirin and SAH (OR 0.68 [0.48, 0.96]). However, populations were diverse and heterogeneity between studies high (p<0.00001), questioning the validity of combining these studies and justifying analysis by population. In the general population there was no difference in aspirin use between individuals with and without SAH (OR 1.15 [0.96, 1.38]). In patients with intracranial aneurysms, aspirin use was greater in patients without SAH (OR 0.37 [0.24, 0.58]), although these studies were at higher risk of bias. Conclusions There is an association between aspirin use and SAH in patients with intracranial aneurysms. This apparent protective relationship is not seen in the general population. Prospective randomised studies are required to further investigate the effect of aspirin on unruptured intracranial aneurysms.


Author(s):  
Ryan D McMullan ◽  
Rachel Urwin ◽  
Peter Gates ◽  
Neroli Sunderland ◽  
Johanna I Westbrook

Abstract Background The operating room (OR) is a complex environment in which distractions, interruptions, and disruptions (DIDs) are frequent. Our aim was to synthesise research on the relationships between DIDs and (a) operative duration, (b) team performance, (c) individual performance, and (d) patient safety outcomes; in order to better understand how interventions can be designed to mitigate the negative effects of DIDs. Methods Electronic databases (MEDLINE, Embase, CINAHL, PsycINFO) and reference lists were systematically searched. Included studies were required to report quantitative outcomes of the association between DIDs and team performance, individual performance, and patient safety. Two reviewers independently screened articles for inclusion, assessed study quality, and extracted data. A random effects meta-analysis was performed on a subset of studies reporting total operative time and DIDs. Results Twenty-seven studies were identified. The majority were prospective observational studies (n=15), of moderate quality (n=15). DIDs were often defined, measured, and interpreted differently in studies. DIDs were significantly associated with: extended operative duration (n=8), impaired team performance (n=6), self-reported errors by colleagues (n=1), surgical errors (n=1), increased risk and incidence of surgical site infection (n=4), and fewer patient safety checks (n=1). A random effects meta-analysis showed that the proportion of total operative time due to DIDs was 22.0% (95% CI 15.7-29.9). Conclusion DIDs in surgery are associated with a range of negative outcomes. However, significant knowledge gaps exist about the mechanisms that underlie these relationships, as well as the potential clinical and non-clinical benefits that DIDs may deliver. Available evidence indicates that interventions to reduce the negative effects of DIDs are warranted, but current evidence is not sufficient to make recommendations about potentially useful interventions.


2021 ◽  
pp. 219256822110308
Author(s):  
Andrew Platt ◽  
Mostafa H. El Dafrawy ◽  
Michael J. Lee ◽  
Martin H. Herman ◽  
Edwin Ramos

Study Design: Systematic review and meta-analysis. Objectives: Indications for surgical decompression of gunshot wounds to the lumbosacral spine are controversial and based on limited data. Methods: A systematic review of literature was conducted to identify studies that directly compare neurologic outcomes following operative and non-operative management of gunshot wounds to the lumbosacral spine. Studies were evaluated for degree of neurologic improvement, complications, and antibiotic usage. An odds ratio and 95% confidence interval were calculated for dichotomous outcomes which were then pooled by random-effects model meta-analysis. Results: Five studies were included that met inclusion criteria. The total rate of neurologic improvement was 72.3% following surgical intervention and 61.7% following non-operative intervention. A random-effects model meta-analysis was carried out which failed to show a statistically significant difference in the rate of neurologic improvement between surgical and non-operative intervention (OR 1.07; 95% CI 0.45, 2.53; P = 0.88). In civilian only studies, a random-effects model meta-analysis failed to show a statistically significant difference in the rate of neurologic improvement between surgical and non-operative intervention (OR 0.75; 95% CI 0.21, 2.72; P = 0.66). Meta-analysis further failed to show a statistically significant difference in the rate of neurologic improvement between patients with either complete (OR 4.13; 95% CI 0.55, 30.80; P = 0.17) or incomplete (OR 0.38; 95% CI 0.10, 1.52; P = 0.17) neurologic injuries who underwent surgical and non-operative intervention. There were no significant differences in the number of infections and other complications between patients who underwent surgical and non-operative intervention. Conclusions: There were no statistically significant differences in the rate of neurologic improvement between those who underwent surgical or non-operative intervention. Further research is necessary to determine if surgical intervention for gunshot wounds to the lumbosacral spine, including in the case of retained bullet within the spinal canal, is efficacious.


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