Brain activations associated with anticipation and delivery of monetary reward: A systematic review and meta-analysis of fMRI studies

Background While multiple studies have examined the brain functional correlates of reward, meta-analyses have either focused on studies using the monetary incentive delay (MID) task, or have adopted a broad strategy, combining data from studies using both monetary and non-monetary reward, as probed using a wide range of tasks. Objective To meta-analyze fMRI studies that used monetary reward and in which there was a definable cue-reward contingency. Studies were limited to those using monetary reward in order to avoid potential heterogeneity from use of other rewards, especially social rewards. Studies using gambling or delay discounting tasks were excluded on the grounds that reward anticipation is not easily quantifiable. Study eligibility English-language fMRI studies (i) that reported fMRI findings on healthy adults; (ii) that used monetary reward; and (iii) in which a cue that was predictive of reward was compared to a no win (or lesser win) condition. Only voxel-based studies were included; those where brain coverage was incomplete were excluded. Data sources Ovid, Medline and PsycInfo, from 2000 to 2020, plus checking of review articles and meta-analyses. Data synthesis Data were pooled using Seed-based d Mapping with Permutation of Subject Images (SDM-PSI). Heterogeneity among studies was examined using the I2 statistic. Publication bias was examined using funnel plots and statistical examination of asymmetries. Moderator variables including whether the task was pre-learnt, sex distribution, amount of money won and width of smoothing kernel were examined. Results Pooled data from 45 studies of reward anticipation revealed activations in the ventral striatum, the middle cingulate cortex/supplementary motor area and the insula. Pooled data from 28 studies of reward delivery again revealed ventral striatal activation, plus cortical activations in the anterior and posterior cingulate cortex. There was relatively little evidence of publication bias. Among moderating variables, only whether the task was pre-learnt exerted an influence. Conclusions According to this meta-analysis monetary reward anticipation and delivery both activate the ventral but not the dorsal striatum, and are associated with different patterns of cortical activation.

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Identification of and Correction for Publication Bias: Comment

10.31222/osf.io/dh87m ◽

2019 ◽

Author(s):

Amanda Kvarven ◽

Eirik Strømland ◽

Magnus Johannesson

Keyword(s):

Publication Bias ◽

False Positive ◽

Large Scale ◽

Meta Analysis ◽

False Positive Rate ◽

Effect Sizes ◽

Replication Studies ◽

Moderate Reduction ◽

Positive Rate ◽

Meta Analyses

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%.

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Leishmanicidal effects of resveratrol and its derivatives: a systematic review and meta-Analysis

10.21203/rs.3.rs-25274/v1 ◽

2020 ◽

Author(s):

Nasrin Amiri Dashatan ◽

Marzieh Ashrafmansouri ◽

Mehdi Koushki ◽

Nayebali Ahmadi

Keyword(s):

Systematic Review ◽

Publication Bias ◽

Data Extraction ◽

Meta Analysis ◽

Sensitivity Analyses ◽

Protective Effects ◽

Random Effects Models ◽

Important Health ◽

Mean Differences ◽

Meta Analyses

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.

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Comparing Bayesian Posterior Passing with Meta-analysis

10.31234/osf.io/ke9wn ◽

2020 ◽

Author(s):

Joshua Pritsker

Keyword(s):

Publication Bias ◽

Fixed Effects ◽

Meta Analysis ◽

Future Research ◽

Meta Analyses

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.

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Global Burden of Anxiety and Depression among Cystic Fibrosis Patient: Systematic Review and Meta-Analysis

International Journal of Chronic Diseases ◽

10.1155/2021/6708865 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Mistire Teshome Guta ◽

Tiwabwork Tekalign ◽

Nefsu Awoke ◽

Robera Olana Fite ◽

Getahun Dendir ◽

...

Keyword(s):

Cystic Fibrosis ◽

North America ◽

Publication Bias ◽

Meta Analysis ◽

Systemic Review ◽

Anxiety And Depression ◽

Close Monitoring ◽

The World ◽

Trim And Fill ◽

Meta Analyses

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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Effects of the endocrine disruptor vinclozolin in male reproduction: a systematic review and meta-analysis†

Biology of Reproduction ◽

10.1093/biolre/ioab018 ◽

2021 ◽

Author(s):

Mariana Feijó ◽

Roberta V L Martins ◽

Sílvia Socorro ◽

Luísa Pereira ◽

Sara Correia

Keyword(s):

Systematic Review ◽

Publication Bias ◽

Meta Analysis ◽

Endocrine Disrupting Chemicals ◽

Reproductive Organs ◽

Male Reproduction ◽

Mean Differences ◽

Trim And Fill ◽

Meta Analyses ◽

Q Statistic

Abstract Endocrine-disrupting chemicals have become an issue of scientific and public discussion. Vinclozolin (VNZ) is a fungicide that competitively antagonizes the binding of natural androgens to their receptor, disturbing the function of tissues that are sensitive to these hormones, as is the case of the male reproductive organs. A systematic review with meta-analyses of rodent studies was conducted to answer the following question: Does exposure to VNZ affect sperm parameters and testicular/epididymal weight? The methodology was prespecified according to the Cochrane Handbook for Systematic Reviews and PRISMA recommendations. Sixteen articles met the inclusion criteria, comprising a total of 1189 animals. The risk of publication bias was assessed using the Trim and Fill adjustment, funnel plot, and Egger regression test. Heterogeneity and inconsistency across the findings were tested using the Q-statistic and I2 of Higgins, respectively. Sensitivity was also analyzed. Statistical analysis was performed on Comprehensive Meta-Analysis software (Version 2.0), using random models and weighted mean differences along with a 95% confidence interval. Sperm motility, counts, daily sperm production (evidence of publication bias), and epididymis weight were decreased in VNZ-treated animals. Exposure length and dose, as well as the time point of exposure, influenced the obtained results. Despite the moderate/high heterogeneity observed, the sensitivity analysis overall demonstrated the robustness of the findings. The quality scores of the included studies were superior to 4 in a total of 9, then classified as good. The obtained data corroborate the capability of VNZ exposure to disrupt spermatogenic output and compromise male fertility.

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SEARCH PROCEDURE AND DATA EXTRACTION FOR META-ANALYSIS IN BIOMEDICAL RESEARCH

10.46793/iccbi21.190o ◽

2021 ◽

Author(s):

Jasmina Obradovic ◽

◽

Vladimir Jurisic

Keyword(s):

Biomedical Research ◽

Data Extraction ◽

Meta Analysis ◽

Extraction Procedure ◽

Microsoft Excel ◽

Pooled Data ◽

Reference Manager ◽

Reference Number ◽

Meta Analyses ◽

Precise Time

The meta-analysis provides a unique scientific conclusion with precise statistical analysis of pooled data extracted from previously reported relevant studies. That gives a better insight into the current issue with more statistical certainty than any single study observation in biomedical research. Occasionally, meta-analyses don’t provide a precise time for each step of the search strategy. The complete meta-analysis procedure is usually time-consuming, with 6-18 months reported, but it depends on the numbers of collected articles manually reviewed by two or more researchers to prevent potential bias. The purpose of this paper was to present a part of meta-analysis research with a focus on a timeline manner for extraction procedure and suggestions for preparing the database of collected articles. PRISMA guidelines were followed, and Pub Med, Scopus, and ISI Web of Science for the search were used. EndNote reference manager v.7 and Microsoft Excel 2007 were used for base preparation. Results showed that the final reference number was 4918, and 99.88% of them were excluded. A month was necessary for the search of the electronic databases. For reading titles and abstracts and extracting the papers was needed the fourth month. A month was needed for an additional search of bibliographies of the eligible papers. Even with the dedication of the team of reviewers, it is hard to predict the exact time for conducting the meta-analysis, indeed. Our results could be applicable in planning the potential systematic reviews, with or without meta-analysis, and overcoming the obstacles in the single database preparation.

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

European Psychiatry ◽

10.1016/j.eurpsy.2005.03.011 ◽

2005 ◽

Vol 20 (8) ◽

pp. 550-553 ◽

Cited By ~ 31

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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Altered central and blood glutathione in Alzheimer Disease and Mild Cognitive Impairment: a meta-analysis

10.21203/rs.3.rs-430047/v1 ◽

2021 ◽

Author(s):

Jinghan J Chen ◽

Mathura Thiyagarajah ◽

Jianmeng Song ◽

Clara Chen ◽

Nathan Herrmann ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Alzheimer Disease ◽

Publication Bias ◽

Subgroup Analysis ◽

Meta Analysis ◽

Random Effects Models ◽

Mean Differences ◽

Meta Analyses

Abstract Background: Increasing evidence implicates oxidative stress (OS) in Alzheimer Disease (AD) and Mild Cognitive Impairment (MCI). Depletion of the brain antioxidant glutathione (GSH) may be important in OS-mediated neurodegeneration, though studies of post-mortem brain GSH changes in AD have been inconclusive. Recent in vivo measurements of brain and blood GSH may shed light on GSH changes earlier in the disease.Aim: To quantitatively review in vivo GSH in AD and MCI compared to healthy controls (HC) using meta-analyses. Method: Studies with in vivo brain or blood GSH levels in MCI or AD with a HC group were identified using Medline, PsychInfo, and Embase (1947-June 2020). Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated for outcomes using random effects models. Outcome measures included brain GSH (Meshcher-Garwood Point Resolved Spectroscopy (MEGA-PRESS) versus non-MEGA-PRESS), and blood GSH (intracellular versus extracellular) in AD and MCI. The Q statistic and Egger’s test were used to assess heterogeneity and risk of publication bias, respectively. Results: For brain GSH, 4 AD (AD=135, HC=223) and 4 MCI (MCI=213, HC=211) studies were included. For blood GSH, 26 AD (AD=1203, HC=1135) and 7 MCI (MCI=434, HC=408) studies were included. Brain GSH overall did not differ in AD or MCI compared to HC; however, the subgroup of studies using MEGA-PRESS reported lower brain GSH in AD (SMD [95%CI] -1.45 [-1.83, -1.06], p<0.001) and MCI (-1.15 [-1.71, -0.59], z=4.0, p<0.001). AD had lower intracellular and extracellular blood GSH overall (-1.10 [-1.58, -0.62], z=4.46, p<0.001). In a subgroup analysis, intracellular GSH was lower in MCI (-0.66 [-1.11, -0.21], p=0.025). Heterogeneity was observed throughout (I2 >85%) and not fully accounted by subgroup analysis. Egger’s test indicated risk of publication bias.Conclusion: Blood intracellular GSH decrease is seen in MCI, while both intra- and extracellular decreases were seen in AD. Brain GSH is decreased in AD and MCI in subgroup analysis. Potential bias and heterogeneity suggest the need for measurement standardization and additional studies to explore sources of heterogeneity.

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Concordance and incongruence in preclinical anxiety models: systematic review and meta-analyses

10.1101/020701 ◽

2015 ◽

Cited By ~ 1

Author(s):

Farhan Mohammad ◽

Joses Ho ◽

Jia Hern Woo ◽

Chun Lei Lim ◽

Dennis Jun Jie Poon ◽

...

Keyword(s):

Systematic Review ◽

Publication Bias ◽

Social Isolation ◽

Gene Knockout ◽

Meta Analysis ◽

Receptor Gene ◽

List Type ◽

Clinical Use ◽

Defense Behavior ◽

Meta Analyses

AbstractRodent defense behavior assays have been widely used as preclinical models of anxiety to study possibly therapeutic anxiety-reducing interventions. However, some proposed anxiety-modulating factors—genes, drugs and stressors—have had discordant effects across different studies. To reconcile the effect sizes of purported anxiety factors, we conducted systematic review and meta-analyses of the literature on ten anxiety-linked interventions, as examined in the elevated plus maze, open field and light-dark box assays. Diazepam, 5-HT1A receptor gene knockout and overexpression, SERT gene knockout and overexpression, pain, restraint, social isolation, corticotropin-releasing hormone and Crhr1 were selected for review. Eight interventions had statistically significant effects on rodent anxiety, while Htr1a overexpression and Crh knockout did not. Evidence for publication bias was found in the diazepam, Htt knockout, and social isolation literatures. The Htr1a and Crhr1 results indicate a disconnect between preclinical science and clinical research. Furthermore, the meta-analytic data confirmed that genetic SERT anxiety effects were paradoxical in the context of the clinical use of SERT inhibitors to reduce anxiety.HighlightsMeta-analysis shows eight rodent anxiety factors have at least moderate effects.Publication bias affects four of the anxiety interventions.Preclinical rodent anxiety results appear disconnected from clinical efforts.Serotonin transporter gene lesion effects are paradoxical with reuptake inhibitors clinical use.

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Prevalence of Calf Mortality in Ethiopia: A Systematic Review and Meta-Analysis

Veterinary Medicine International ◽

10.1155/2021/6677986 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Ephrem Tora ◽

Mesfin Shrube ◽

Tamirat Kaba ◽

Wasihun Seyoum

Keyword(s):

Systematic Review ◽

Publication Bias ◽

Meta Analysis ◽

Random Effect Model ◽

Dairy Industry ◽

Economic Losses ◽

Original Research ◽

Pooled Prevalence ◽

Wide Range ◽

Calf Mortality

Background. Calf mortality has been a major cause of economic losses in the dairy industry in Ethiopia. The condition results in a significant drop in the number of replacing heifers and bulls for sustainable dairy business. Reports on calf mortality with a wide range of prevalence are rising in the country; however, a pooled prevalence of this condition has not been established. Thus, this systematic review and meta-analysis aimed to quantitatively estimate the pooled prevalence of calf mortality in Ethiopia. Methods. Meta-analysis was carried out to obtain the pooled prevalence of calf mortality in Ethiopia. A comprehensive literature search was carried out on PubMed, African Journals Online, CAB, Web of Science Direct, and Google Scholar. Eligible studies were selected based on predefined inclusion and exclusion criteria. Moderators such as the study area, breed of calf, study design, agroecology, and year of study article published were used as a milestone of data extraction. The random-effect model was used to estimate pooled prevalence. Publication bias and the variation in prevalence estimates attributed to heterogeneity were also assessed. Results. Twenty-five original research papers on the prevalence of calf mortality in various parts of Ethiopia were included. The reported prevalence of calf mortality was between 0.9% and 37%. The pooled prevalence of calf mortality in the country was 14.79%, and the pooled calf mortality estimate across studies for the entire period regarding 1991 to 2000, 2001 to 2010, 2011 to 2016, and 2017 to 2020 was 26.54%, 17.03%, 14.21%, and 11.23%, respectively. Analysis of study subgroups and location revealed significant variations in prevalence. High heterogeneity was observed in the pooled estimates and even after the subgroup meta-analysis. The funnel plots and Egger’s regression asymmetry coefficient (b = −1.0434) (95% CI = −1.49, −0.59; p value of 0.012) did suggest the presence of publication bias. There was also an indication of missing studies that could be incorporated by Duval and Tweedie’s trim and fill method where they might fall on a funnel plot and visualize them in an attempt to increase the plot’s symmetry. Analyses also suggest that calf breed, sample size, and study location are likely to be moderators of calf mortality prevalence in Ethiopia. Conclusion. This finding shows that calf mortality is widespread and could result in considerable economic losses for the dairy industry in Ethiopia. Inevitably, a significant reduction in calf mortality prevalence has been observed in recent years since 2010, but the reduction has not yet reached an economically tolerable level. Calf breed susceptibility contributed to the high prevalence. Therefore, interventions for increasing calf health and performance should be focused on minimizing calf mortality on farm and animal levels.

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