scholarly journals Comparing Bayesian Posterior Passing with Meta-analysis

2020 ◽  
Author(s):  
Joshua Pritsker

Brand, von der Post, Ounsley, and Morgan (2019) introduced Bayesian posterior passing as an alternative to traditional meta-analyses. In this commentary I relate their procedure to traditional meta-analysis, showing that posterior passing is equivalent to fixed effects meta-analysis. To overcome the limitations of simple posterior passing, I introduce improved posterior passing methods to account for heterogeneity and publication bias. Additionally, practical limitations of posterior passing and the role that it can play in future research are discussed.

2021 ◽  
Vol 5 ◽  
Author(s):  
Joshua Pritsker

Brand, von der Post, Ounsley, and Morgan (2019) introduced Bayesian posterior passing as an alternative to traditional meta-analyses.  In this commentary I relate their procedure to traditional meta-analysis, showing that posterior passing is equivalent to fixed effects meta-analysis.  To overcome the limitations of simple posterior passing, I introduce improved posterior passing methods to account for heterogeneity and publication bias.  Additionally, practical limitations of posterior passing and the role that it can play in future research are discussed.


2016 ◽  
Vol 77 (3) ◽  
pp. 449-470 ◽  
Author(s):  
William R. Nugent

Meta-analysis is a significant methodological advance that is increasingly important in research synthesis. Fundamental to meta-analysis is the presumption that effect sizes, such as the standardized mean difference (SMD), based on scores from different measures are comparable. It has been argued that population observed score SMDs based on scores from different measures A and B will be equal only if the conjunction of three conditions are met: construct equivalence (CE), equal reliabilities (ER), and the absence of differential test functioning (DTF) in all subpopulations of the combined populations of interest. It has also been speculated the results of a meta-analysis of SMDs might differ between circumstances in which the SMDs included in a meta-analysis are based on measures which all met the conjunction of these conditions and that in which the conjunction of these conditions is violated. No previous studies have tested this conjecture. This Monte Carlo study investigated this hypothesis. A population of studies comparing one of five hypothetical treatments with a placebo condition was simulated. The SMDs in these simulated studies were based on true scores from six hypothetical measures. The scores from some of these measures met the conjunction of CE, ER, and, the absence of DTF, while others failed to meet CE. Three meta-analyses were conducted using both fixed effects and random effects methods. The results suggested that the results of meta-analyses can vary to a practically significant degree when the SMDs were based on scores from measures failing to meet the CE condition. Implications for future research are considered.


Author(s):  
Janet L. Peacock ◽  
Philip J. Peacock

Meta-analysis: introduction 448 Searching for studies 450 Combining estimates in meta-analyses 452 Heterogeneity 454 Overcoming heterogeneity 456 Fixed effects estimates 458 Random effects estimates 460 Presenting meta-analyses 462 Publication bias 464 Detecting publication bias 466 Adjusting for publication bias 468 Independent patient data meta-analysis 472...


2019 ◽  
Author(s):  
Amanda Kvarven ◽  
Eirik Strømland ◽  
Magnus Johannesson

Andrews & Kasy (2019) propose an approach for adjusting effect sizes in meta-analysis for publication bias. We use the Andrews-Kasy estimator to adjust the result of 15 meta-analyses and compare the adjusted results to 15 large-scale multiple labs replication studies estimating the same effects. The pre-registered replications provide precisely estimated effect sizes, which do not suffer from publication bias. The Andrews-Kasy approach leads to a moderate reduction of the inflated effect sizes in the meta-analyses. However, the approach still overestimates effect sizes by a factor of about two or more and has an estimated false positive rate of between 57% and 100%.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jing Li ◽  
Yinzi Chen ◽  
Xiling Wang ◽  
Hongjie Yu

AbstractInfluenza causes substantial morbidity and mortality. Many original studies have been carried out to estimate disease burden of influenza in mainland China, while the full disease burden has not yet been systematically reviewed. We did a systematic review and meta-analysis to assess the burden of influenza-associated mortality, hospitalization, and outpatient visit in mainland China. We searched 3 English and 4 Chinese databases with studies published from 2005 to 2019. Studies reporting population-based rates of mortality, hospitalization, or outpatient visit attributed to seasonal influenza were included in the analysis. Fixed-effects or random-effects model was used to calculate pooled estimates of influenza-associated mortality depending on the degree of heterogeneity. Meta-regression was applied to explore the sources of heterogeneity. Publication bias was assessed by funnel plots and Egger’s test. We identified 30 studies eligible for inclusion with 17, 8, 5 studies reporting mortality, hospitalization, and outpatient visit associated with influenza, respectively. The pooled influenza-associated all-cause mortality rates were 14.33 and 122.79 per 100,000 persons for all ages and ≥ 65 years age groups, respectively. Studies were highly heterogeneous in aspects of age group, cause of death, statistical model, geographic location, and study period, and these factors could explain 60.14% of the heterogeneity in influenza-associated mortality. No significant publication bias existed in estimates of influenza-associated all-cause mortality. Children aged < 5 years were observed with the highest rates of influenza-associated hospitalizations and ILI outpatient visits. People aged ≥ 65 years and < 5 years contribute mostly to mortality and morbidity burden due to influenza, which calls for targeted vaccination policy for older adults and younger children in mainland China.


2014 ◽  
Vol 205 (5) ◽  
pp. 340-347 ◽  
Author(s):  
Christian Loret De Mola ◽  
Giovanny Vinícius Araújo De França ◽  
Luciana de Avila Quevedo ◽  
Bernardo Lessa Horta

BackgroundThere is no consensus on the effects that low birth weight, premature birth and intrauterine growth have on later depression.AimsTo review systematically the evidence on the relationship of low birth weight, smallness for gestational age (SGA) and premature birth with adult depression.MethodWe searched the literature for original studies assessing the effect of low birth weight, premature birth and SGA on adult depression. Separate meta-analyses were carried out for each exposure using random and fixed effects models. We evaluated the contribution of methodological covariates to heterogeneity using meta-regression.ResultsWe identified 14 studies evaluating low birth weight, 9 premature birth and 4 SGA. Low birth weight increased the odds of depression (OR = 1.39, 95% CI 1.21–1.60). Premature birth and SGA were not associated with depression, but publication bias might have underestimated the effect of the former and only four studies evaluated SGA.ConclusionsLow birth weight was associated with depression. Future studies evaluating premature birth and SGA are needed.


2005 ◽  
Vol 23 (34) ◽  
pp. 8606-8612 ◽  
Author(s):  
Stefanos Bonovas ◽  
Kalitsa Filioussi ◽  
Nikolaos Tsavaris ◽  
Nikolaos M. Sitaras

Purpose A growing body of evidence suggests that statins may have chemopreventive potential against breast cancer. Laboratory studies demonstrate that statins induce apoptosis and reduce cell invasiveness in various cell lines, including breast carcinoma cells. However, the clinical relevance of these data remains unclear. The nonconclusive nature of the epidemiologic data prompted us to conduct a detailed meta-analysis of the studies published on the subject in peer-reviewed literature. Patients and Methods A comprehensive search for articles published up until 2005 was performed; reviews of each study were conducted; and data were abstracted. Before meta-analysis, the studies were evaluated for publication bias and heterogeneity. Pooled relative risk (RR) estimates and 95% CIs were calculated using the random and the fixed-effects models. Subgroup and sensitivity analyses were also performed. Results Seven large randomized trials and nine observational studies (five case-control and four cohort studies) contributed to the analysis. We found no evidence of publication bias or heterogeneity among the studies. Statin use did not significantly affect breast cancer risk (fixed effects model: RR = 1.03; 95% CI, 0.93 to 1.14; random effects model: RR = 1.02; 95% CI, 0.89 to 1.18). When the analyses were stratified into subgroups, there was no evidence that study design substantially influenced the estimate of effects. Furthermore, the sensitivity analysis confirmed the stability of our results. Conclusion Our meta-analysis findings do not support a protective effect of statins against breast cancer. However, this conclusion is limited by the relatively short follow-up times of the studies analyzed. Further studies are required to investigate the potential decrease in breast cancer risk among long-term statin users.


2017 ◽  
Vol 26 (3) ◽  
pp. 143-155 ◽  
Author(s):  
Stephen P. Kilgus ◽  
Katie Eklund ◽  
Daniel M. Maggin ◽  
Crystal N. Taylor ◽  
Amanda N. Allen

The purpose of this study was to conduct reliability and validity generalization meta-analyses of evidence regarding the Student Risk Screening Scale (SRSS), a universal screener for externalizing behavior problems. A systematic review of the literature resulted in the identification of 17 studies inclusive of evidence regarding SRSS score (a) internal consistency reliability (i.e., alpha coefficients), and/or (b) criterion-related validity (e.g., correlations between the SRSS and various outcomes). Multilevel meta-analyses indicated that across studies, SRSS scores were associated with adequate internal consistency (α = .83). Analyses further suggested the SRSS was a valid indicator of both social and behavioral outcomes ( r = .52) and academic outcomes ( r = .42). Follow-up analyses suggested that in accordance with theory-driven expectations, the SRSS was a stronger indicator of externalizing problems and broad behavior outcomes relative to alternative outcomes (e.g., internalizing problems). Limitations and directions for future research are discussed, including recommendations for the collection of additional SRSS diagnostic accuracy evidence.


2020 ◽  
Author(s):  
Nasrin Amiri Dashatan ◽  
Marzieh Ashrafmansouri ◽  
Mehdi Koushki ◽  
Nayebali Ahmadi

Abstract Background Leishmaniasis is one of the most important health problems worldwide. The evidence has suggested that resveratrol and its derivatives have anti-leishmanial effects; however, the results are inconsistent and inconclusive. The aim of this study was to assess the effect of resveratrol and its derivatives on the Leishmania viability through a systematic review and meta-analysis of available relevant studies. Methods The electronic databases PubMed, ScienceDirect, Embase, Web of Science and Scopus were queried between October 2000 and April 2020 using a comprehensive search strategy. The eligible articles selected and data extraction conducted by two reviewers. Mean differences of IC50 (concentration leading to reduction of 50% of Leishmania) for each outcome was calculated using random-effects models. Sensitivity analyses and prespecified subgroup were conducted to evaluate potential heterogeneity and the stability of the pooled results. Publication bias was evaluated using the Egger’s and Begg’s tests. We also followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines for this review. Results Ten studies were included in the meta-analysis. We observed that RSV and its derivatives had significant reducing effects on Leishmania viability in promastigote [24.02 µg/ml; (95% CI 17.1, 30.8); P < 0.05; I2 = 99.8%; P heterogeneity = 0.00] and amastigote [18.3 µg/ml; (95% CI 13.5, 23.2); P < 0.05; I2 = 99.6%; P heterogeneity = 0.00] stages of Leishmania. A significant publication bias was observed in the meta-analysis. Sensitivity analyses showed a similar effect size while reducing the heterogeneity. Subgroup analysis indicated that the pooled effects of leishmanicidal of resveratrol and its derivatives were affected by type of stilbenes and Leishmania species. Conclusions Our findings clearly suggest that the strategies for the treatment of leishmaniasis should be focused on natural products such as RSV and its derivatives. Further study is needed to identify the mechanisms mediating this protective effects of RSV and its derivatives in leishmaniasis.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Mistire Teshome Guta ◽  
Tiwabwork Tekalign ◽  
Nefsu Awoke ◽  
Robera Olana Fite ◽  
Getahun Dendir ◽  
...  

Aims. This systemic review and meta-analysis were aimed at determining the level of anxiety and depression among cystic fibrosis patients in the world. Methods. We conducted a systematic search of published studies from PubMed, EMBASE, MEDLINE, Cochrane, Scopus, Web of Science, CINAHL, and manually on Google Scholar. This meta-analysis follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of studies was assessed by the modified Newcastle-Ottawa Scale (NOS). Meta-analysis was carried out using a random-effects method using the STATA™ Version 14 software. Trim and fill analysis was done to correct the presence of significant publication bias. Result. From 419,820 obtained studies, 26 studies from 2 different parts of the world including 9766. The overall global pooled prevalence of anxiety and depression after correction for publication bias by trim and fill analysis was found to be 24.91(95% CI: 20.8-28.9) for anxiety. The subgroup analyses revealed with the lowest prevalence, 23.59%, (95% CI: 8.08, 39.09)) in North America and the highest, 26.77%, (95% CI: 22.5, 31.04) seen in Europe for anxiety and with the highest prevalence, 18.67%, (95% CI: 9.82, 27.5) in North America and the lowest, 13.27%, (95% CI: -10.05, 16.5) seen in Europe for depression. Conclusion. The global prevalence of anxiety and depression among cystic fibrosis patients is common. Therefore, close monitoring of the patient, regularly screening for anxiety and depression, and appropriate prevention techniques is recommended.


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