Confidence intervals for random effects meta-analysis and robustness to publication bias

The effectiveness of couples' lifestyle interventions on weight change: A systematic review and meta-analysis of Randomised Controlled Trials

Introduction: Lifestyle interventions aiming to reduce excess body weight have been focusing on individuals living with overweight or obesity. However, many health-related behaviors including eating are concordant in couples indicating they might share an obesity risk or support each other's weight loss efforts. Aim: The aim of this systematic review and meta-analysis of randomized controlled trials was to assess the weight change effects of lifestyle interventions targeting couples in a romantic relationship regardless of marital status or sexual preference compared to individuals or no intervention. Methods: Four databases (MEDLINE Ovid, Scopus, CINHAL, and mySearch: EBSCO-Discovery-Service-Tool) were systematically searched from inception until 26th April 2021 with further email alerts. The risk of bias was assessed using the Critical Appraisal Skills Programme. Meta-analysis was conducted using the random-effect model to estimate the weighted mean difference with 95% confidence interval. Results: Seventeen studies were eligible for this review and 11 of them were included in the meta-analysis for weight change. Significant intervention effects were identified for body weight in couples' intervention vs. individual intervention (-2.25 kg, 95% CI-3.63 to-0.88), and vs. no intervention (-4.5 kg, 95% CI-6.62 to-2.38). Conclusion: This systematic review and meta-analysis was the first to investigate the effectiveness of lifestyle interventions targeting couples on weight loss, compared to interventions focused on individuals or standard care. The findings suggest that interventions aimed at couples lead to greater weight loss, though the results should be interpreted with caution due to the wide heterogeneity among the studies. Further research is needed with evidence-based study designs, targeting younger participants, and incorporating longer intervention durations and follow-up periods.

A brief note on the random-effects meta-analysis model and its relationship to other models

Meta-analysis is a statistical method for combining quantitative results across studies. A fundamental decision in undertaking a meta-analysis is choosing an appropriate model for analysis. This is the second of two companion articles which have the joint aim of describing the different meta-analysis models. In the first article, we focused on the common-effect (also known as fixed-effect [singular]) model, and in this article, we focus on the random-effects model. We describe the key assumptions underlying the random-effects model, how it is related to the common-effect and fixed-effects [plural] models, and present some of the arguments for selecting one model over another. We outline some of the methods for fitting a random-effects model. Finally, we present an illustrative example to demonstrate how the results can differ depending on the chosen model and method. Understanding the assumptions of the different meta-analysis models, and the questions they address, is critical for meta-analysis model selection and interpretation.

A systematic review and meta-analysis of the parental stress scale's psychometric properties

Parental stress can affect the ability of parents to cope with the challenges of raising children. The result can be a negative cycle within the family dynamic, which in turn can interfere with children's development and emotional regulation. Among the many instruments available to assess parental stress, the Parental Stress Scale (PSS) deserves particular mention. To our knowledge, there are currently no systematic reviews evaluating the psychometric properties of the PSS. The aim of this systematic review was to assess the psychometric properties of the PSS using the COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) methodology and to conduct a meta-analysis. A thorough literature search was conducted from different databases. A meta-analysis to test the generalisability of PSS internal consistency across its component factors was performed. A total of 20 validation studies of the PSS were identified. Based on the COSMIN methodology, this instrument receives an 'A' rating, meaning that it is considered to be a cross-sectional instrument with the necessary scientific evidence for the assessment of the construct of parental stress. The meta-analysis testing the generalisability of its internal consistency yielded satisfactory results across the different factors. Future research should focus on those psychometric properties of the PSS that have not been studied as extensively, such as reproducibility, responsiveness, measurement error, and measurement invariance.

A Meta-Analysis of Interpersonal and Psychodynamic Psychotherapies for Posttraumatic Stress Disorder

OBJECTIVE

Established trauma-focused cognitive-behavioral therapies for posttraumatic stress disorder (PTSD) have remission rates of approximately 30%-40%. Alternatively, interpersonal psychotherapy (IPT) and psychodynamic psychotherapy (PDT) focus on disrupted attachment, mentalization, and social connection in PTSD and may help some patients. The authors conducted a meta-analysis on these interpersonal and affect-oriented approaches to treating PTSD.

METHODS

Building on a prior meta-analysis, the authors searched for randomized controlled trials (RCTs) comparing IPT or PDT with other established PTSD treatments or control conditions for adults diagnosed as having PTSD. Random-effects meta-analyses were conducted to assess outcome effect sizes and dropout rates. RCTs were rated via the Randomized Controlled Trial Psychotherapy Quality Rating Scale.

RESULTS

Ten RCTs (eight of IPT) comparing IPT or PDT with control (k=7) or active treatment (k=4) conditions were identified, nine of which were of adequate quality. IPT (k=5) and PDT (k=2), when analyzed together, were superior to control conditions overall (g=-1.14, p=0.011 [as was IPT alone: g=-0.88, p=0.034]) and to waitlist (g=-1.49) and treatment-as-usual (g=-0.70) groups. Effect sizes, however, may have been inflated by outliers or publication bias. IPT (k=3) and PDT (k=1), when analyzed together, were equally efficacious compared with other active PTSD treatments (primarily exposure-based psychotherapies), as was IPT alone, and had lower dropout rates (relative risk=0.63, p=0.049 for IPT and PDT analyzed together; relative risk=0.61, p=0.098 for IPT alone).

CONCLUSIONS

Affect-focused therapies hold promise in the treatment of PTSD. IPT has demonstrated efficacy in multiple trials, whereas the evidence base for PDT is sparse.

Vicarious Dissonance: Pre-Registered Meta-Analysis

The vicarious cognitive dissonance process predicts that observing an inconsistent act by a member of the ingroup causes uncomfortable arousal in the observer, inducing a motivation to reduce this discomfort. This meta-analysis examined the effect of vicarious cognitive dissonance based on 24 studies (N = 16,769). Our results indicated a small effect for the vicarious cognitive dissonance (g = 0.41 [0.27, 0.54], p <.001) with important variability between the outcomes. Our moderator analysis was limited by the low number of included studies. Publication bias analyses indicate a small true effect size (e.g., 3PSM: g = 0.22, p = .042), that was inflated by small sample sizes (R-index = 14.6%). We discussed theoretical issues concerning the psychological processes underlying vicarious cognitive dissonance, and methodological questions concerning operationalization. We proposed ways of improving the design and procedure to ensure that the effects found in the literature exist and are replicable.

Influence of pelvic floor muscle training alone or as part of a general physical activity program during pregnancy on urinary incontinence, episiotomy and third- or fourth-degree perineal tear: Systematic review and meta-analysis of randomized clinical trials

INTRODUCTION

The complex process of pregnancy and childbirth significantly influences the well-being of both mother and child. Today all pregnant women without medical contraindications are recommended to start or continue regular aerobic and strength training for at least 150 min per week to prevent pregnancy-related diseases and conditions. Urinary incontinence in pregnancy, episiotomy and third- or fourth-degree perineal tear during labor can greatly impact womens' health, quality of life and ability to be physically active. The aim of this study was to examine the efficacy of pelvic floor muscle training (PFMT) during pregnancy in the prevention of urinary incontinence, episiotomy, and third- or fourth-degree perineal tear.

MATERIAL AND METHODS

A systematic review and meta-analysis (CRD42022370600) was performed. Only randomized clinical trials published between 2010 and 2023 were included. The following databases were examined: EBSCO (including Academic Search Premier, Education Resources Information Center, MEDLINE, SPORTDiscus and OpenDissertations databases), Clinicaltrials.gov, Web of Science, Scopus, Cochrane Database of Systematic Reviews and Physiotherapy Evidence Database (PEDro). Three meta-analyses to investigate the effect of PFMT exclusively or implemented as a section within a physical activity program during pregnancy on urinary incontinence, episiotomy, and third- or fourth-degree perineal tear were conducted.

RESULTS

Thirty studies were analyzed (N = 6691). An effective preventive action of PFMT was found for urinary incontinence (z = 3.46; p < 0.0005; relative risk [RR] = 0.72, 95% confidence interval [CI]: 0.59, 0.87, I2 = 59%) and third- or fourth-degree perineal tear (z = 2.89; p = 0.004; RR = 0.50, 95% CI: 0.31, 0.80, I2 = 48%) but not for episiotomy (z = 0.80; p = 0.42; RR = 0.95, 95% CI: 0.85, 1.07, I2 = 75%).

CONCLUSIONS

PFMT during pregnancy proves to be an effective preventive intervention for reducing the risk of urinary incontinence and the occurrence of third- or fourth-degree perineal tears. These findings highlight the importance of incorporating PFMT into antenatal care and training programs to improve maternal well-being and overall childbirth outcomes.

Peripheral vascular function in stroke: systematic review and meta-analysis

Peripheral vascular dysfunction, measured as flow-mediated dilation (FMD), is present across all phases of stroke recovery and elevates the risk for recurrent cardiovascular events. The objective of this systematic review and meta-analysis was to characterize baseline FMD in individuals' poststroke, with consideration for each phase of stroke recovery. Three databases (PubMed, CINAHL, and Embase) were searched between January 1, 2000 and October 12, 2023 for studies that examined baseline FMD in stroke. Three reviewers conducted abstract and full-text screening, data extraction, and quality assessment. A random effects model was used to estimate FMD across studies. Meta-regression was used to examine the impact of age and time since stroke (acute, subacute, chronic) on FMD. Twenty-eight studies with ischemic and hemorrhagic stroke were included. Descriptive statistics for the demographics and FMD values of each study are presented. For the meta-analysis, average estimate FMD was 3.9% (95% CI: 2.5-5.3%). We report a large amount of heterogeneity (Cochrane's Q P value <0.001, and I2 = 99.6%). Differences in average age and the time poststroke between studies were not significantly associated with differences in FMD values. Despite the large heterogeneity for FMD values across studies, our primary finding suggests that FMD remains impaired across all phases of stroke.NEW & NOTEWORTHY This systematic review and meta-analysis offers invaluable insight into poststroke vascular function. Despite the inherent heterogeneity among the 28 studies analyzed, we report that peripheral vascular dysfunction, as quantified by flow-mediated dilation, exists across all stages of stroke recovery. This finding underscores the importance for interventions that focus on improving vascular health and secondary stroke prevention.

Tranexamic Acid for Traumatic Injury in the Emergency Setting: A Systematic Review and Bias-Adjusted Meta-Analysis of Randomized Controlled Trials

STUDY OBJECTIVE

Traumatic injury causes a significant number of deaths due to bleeding. Tranexamic acid (TXA), an antifibrinolytic agent, can reduce bleeding in traumatic injuries and potentially enhance outcomes. Previous reviews suggested potential TXA benefits but did not consider the latest trials.

METHODS

A systematic review and bias-adjusted meta-analysis were performed to assess TXA's effectiveness in emergency traumatic injury settings by pooling estimates from randomized controlled trials. Researchers searched Medline, Embase, and Cochrane Central for randomized controlled trials comparing TXA's effects to a placebo in emergency trauma cases. The primary endpoint was 1-month mortality. The methodological quality of the trials underwent assessment using the MASTER scale, and the meta-analysis applied the quality-effects method to adjust for methodological quality.

RESULTS

Seven randomized controlled trials met the set criteria. This meta-analysis indicated an 11% decrease in the death risk at 1 month after TXA use (odds ratio [OR] 0.89, 95% confidence interval [CI] 0.84 to 0.95) with a number needed to treat of 61 to avoid 1 additional death. The meta-analysis also revealed reduced 24-hour mortality (OR 0.76, 95% CI 0.65 to 0.88) for TXA. No compelling evidence of increased vascular occlusive events emerged (OR 0.96, 95% CI 0.73 to 1.27). Subgroup analyses highlighted TXA's effectiveness in general trauma versus traumatic brain injury and survival advantages when administered out-of-hospital versus inhospital.

CONCLUSIONS

This synthesis demonstrates that TXA use for trauma in emergencies leads to a reduction in 1-month mortality, with no significant evidence of problematic vascular occlusive events. Administering TXA in the out-of-hospital setting is associated with reduced mortality compared to inhospital administration, and less mortality with TXA in systemic trauma is noted compared with traumatic brain injury specifically.

Comparison of bias adjustment in meta-analysis using data-based and opinion-based methods

INTRODUCTION

Several methods exist for bias adjustment of meta-analysis results, but there has been no comprehensive comparison with unadjusted methods. We compare 6 bias-adjustment methods with 2 unadjusted methods to examine how these different methods perform.

METHODS

We re-analyzed a meta-analysis that included 10 randomized controlled trials. Two data-based methods (Welton's data-based approach and Doi's quality effects model) and 4 opinion-informed methods (opinion-based approach, opinion-based distributions combined statistically with data-based distributions, numerical opinions informed by data-based distributions, and opinions obtained by selecting areas from data-based distributions) were used to incorporate methodological quality information into the meta-analytical estimates. The results of these 6 methods were compared with 2 unadjusted models: the DerSimonian-Laird random effects model and Doi's inverse variance heterogeneity model.

RESULTS

The 4 opinion-based methods returned the random effects model estimates with wider uncertainty. The data-based and quality effects methods returned different results and aligned with the inverse variance heterogeneity method with some minor downward bias adjustment.

CONCLUSION

Opinion-based methods seem to only add uncertainty rather than bias adjust.

Influence of study characteristics, methodological rigour and publication bias on efficacy of pharmacotherapy in obsessive-compulsive disorder: a systematic review and meta-analysis of randomised, placebo-controlled trials

QUESTION

We examined the effect of study characteristics, risk of bias and publication bias on the efficacy of pharmacotherapy in randomised controlled trials (RCTs) for obsessive-compulsive disorder (OCD).

STUDY SELECTION AND ANALYSIS

We conducted a systematic search of double-blinded, placebo-controlled, short-term RCTs with selective serotonergic reuptake inhibitors (SSRIs) or clomipramine. We performed a random-effect meta-analysis using change in the Yale-Brown Obsessive-Compulsive Scale (YBOCS) as the primary outcome. We performed meta-regression for risk of bias, intervention, sponsor status, number of trial arms, use of placebo run-in, dosing, publication year, age, severity, illness duration and gender distribution. Furthermore, we analysed publication bias using a Bayesian selection model.

FINDINGS

We screened 3729 articles and included 21 studies, with 4102 participants. Meta-analysis showed an effect size of -0.59 (Hedges' G, 95% CI -0.73 to -0.46), equalling a 4.2-point reduction in the YBOCS compared with placebo. The most recent trial was performed in 2007 and most trials were at risk of bias. We found an indication for publication bias, and subsequent correction for this bias resulted in a depleted effect size. In our meta-regression, we found that high risk of bias was associated with a larger effect size. Clomipramine was more effective than SSRIs, even after correcting for risk of bias. After correction for multiple testing, other selected predictors were non-significant.

CONCLUSIONS

Our findings reveal superiority of clomipramine over SSRIs, even after adjusting for risk of bias. Effect sizes may be attenuated when considering publication bias and methodological rigour, emphasising the importance of robust studies to guide clinical utility of OCD pharmacotherapy.

PROSPERO REGISTRATION NUMBER

CRD42023394924.

A systematic review of factors associated with sustained smoking abstinence in people experiencing severe mental illness following participation in a smoking intervention

OBJECTIVE

People experiencing severe mental illness report higher rates of tobacco smoking than the general population, while rates of quitting and sustaining abstinence are considerably lower. This systematic review aimed to identify factors associated with sustained abstinence in people experiencing severe mental illness following a smoking intervention.

METHOD

Searches were conducted in PubMed, PsycInfo, Scopus, Embase, Emcare, CINAHL and Cochrane Library from the inception of the e-databases until June 2022. Selection criteria included randomised and non-randomised studies of smoking cessation interventions in which most of the participants were experiencing severe mental illness, and reported a follow-up of 3 months or longer. From an initial 1498 unique retrieved records, 26 references were included detailing 17 smoking cessation intervention studies and 3 relapse prevention intervention studies. Risk of bias was assessed using the RoB2 tool for randomised study designs and the ROBINS-I tool for non-randomised designs.

RESULTS

Participation in smoking interventions was associated with higher odds of abstinence in the medium-term, but not long-term follow-ups. There was insufficient evidence that any other factors impact sustained abstinence. Most studies were considered to have some risk of bias, largely due to insufficient availability of analysis plans.

CONCLUSION

Despite an abundance of studies investigating smoking cessation in smokers experiencing severe mental illness, there is limited knowledge on the factors associated with staying quit. The inclusion of people experiencing severe mental illness in large-scale randomised control trials, in which predictors of sustained abstinence are measured in the medium and long term are needed to address this important question.

The normality assumption on between-study random effects was questionable in a considerable number of Cochrane meta-analyses

BACKGROUND

Studies included in a meta-analysis are often heterogeneous. The traditional random-effects models assume their true effects to follow a normal distribution, while it is unclear if this critical assumption is practical. Violations of this between-study normality assumption could lead to problematic meta-analytical conclusions. We aimed to empirically examine if this assumption is valid in published meta-analyses.

METHODS

In this cross-sectional study, we collected meta-analyses available in the Cochrane Library with at least 10 studies and with between-study variance estimates > 0. For each extracted meta-analysis, we performed the Shapiro-Wilk (SW) test to quantitatively assess the between-study normality assumption. For binary outcomes, we assessed between-study normality for odds ratios (ORs), relative risks (RRs), and risk differences (RDs). Subgroup analyses based on sample sizes and event rates were used to rule out the potential confounders. In addition, we obtained the quantile-quantile (Q-Q) plot of study-specific standardized residuals for visually assessing between-study normality.

RESULTS

Based on 4234 eligible meta-analyses with binary outcomes and 3433 with non-binary outcomes, the proportion of meta-analyses that had statistically significant non-normality varied from 15.1 to 26.2%. RDs and non-binary outcomes led to more frequent non-normality issues than ORs and RRs. For binary outcomes, the between-study non-normality was more frequently found in meta-analyses with larger sample sizes and event rates away from 0 and 100%. The agreements of assessing the normality between two independent researchers based on Q-Q plots were fair or moderate.

CONCLUSIONS

The between-study normality assumption is commonly violated in Cochrane meta-analyses. This assumption should be routinely assessed when performing a meta-analysis. When it may not hold, alternative meta-analysis methods that do not make this assumption should be considered.

Potential impact of platelet-to-lymphocyte ratio on prognosis in patients with colorectal cancer: A systematic review and meta-analysis

Background

Numerous studies have confirmed that inflammation promotes the occurrence, development and prognosis of colorectal cancer (CRC).

Objective

This study focuses on the potentially prognostic value of the platelet-to-lymphocyte ratio (PLR) in CRC patients.

Data Sources

This study was registered at PROSPERO (ID: CRD42020219215). Relative studies were searched on PubMed, Cochrane Library, Embase, Web of Science, and clinical trial databases by two back-to-back reviewers. Study Selection and Intervention: Studies were screened according to the predetermined inclusion and exclusion criteria, comparing prognosis differences between low PLR levels and high PLR levels for CRC patients. Main Outcome Measures: Studies were integrated and compared to analyze the value of PLR in predicting overall survival (OS), progression-free survival (PFS), cancer-specific survival (CSS), disease-free survival (DFS) and recurrence-free survival (RFS) of CRC. Results: Outcomes were compared using Review Manager (version 5.4) software from Cochrane Collaboration. A total of 27 literary works, including 13,330 patients, were incorporated into our study. The final results showed that higher PLR levels had worse OS (hazard ratio [HR] = 1.40, 95% confidence interval [CI] = 1.21-1.62, P < 0.00001), DFS (HR = 1.44, 95% CI = 1.09-1.90, P = 0.01) and RFS (HR = 1.48, 95% CI = 1.13-1.94, P = 0.005) than lower PLR levels, respectively. However, there was no evidence of significance for PFS (HR = 1.14, 95% CI = 0.84-1.54, P = 0.40) and CSS (HR = 1.16, 95% CI = 0.88-1.53, P = 0.28) in the final meta-analysis.

Limitations

Our study has the following limitations. First of all, we only included literature published in English, which means that some publication bias may be inevitable. In addition, our study used aggregate data, not individual data; furthermore, we did not define the exact cut-off value representing the PLR level.

Conclusion

An elevated PLR seems to be an adverse prognostic factor affecting survival outcomes in patients with CRC. Meanwhile, more prospective studies are required to confirm our conclusion.PROSPERO ID: CRD42020219215.

How efficacious are traditional Chinese medicine injections in treating angina pectoris? A network meta-analysis of randomized controlled trials

ETHNOPHARMACOLOGICAL RELEVANCE

Over 50 million adults in China suffer from angina pectoris, which are often treated with traditional Chinese medicine injections (TCMIs). However, the efficacies of TCMIs and conventional drugs as determined by randomized controlled trials (RCTs) were not rigorously compared with one another by network meta-analysis (NMA). This PRISMA-compliant NMA aimed to compare the efficacy and assess the evidence strengths of 24 TCMIs in treating adults with angina pectoris of RCTs.

MATERIALS AND METHODS

Following the protocol (PROSPERO registration number CRD42018117720), the RCTs that compared any TCMI with another TCMI or conventional drug on outcome measures including symptomatic and electrocardiography improvements were included. The quality of included RCTs was assessed with the Cochrane's risk of bias 2 tool. Frequentist statistical analyses were performed, including NMA, pairwise meta-analysis (PMA), subgroup analysis, sensitivity analysis, meta-regression, and publication bias analysis. The certainty of evidence was assessed with the GRADE approach.

RESULTS

Totally, 556 eligible RCTs with 57015 participants were identified while the quality of all but five included RCTs was poor. The significant efficacy estimates and insignificant heterogeneity assessment from PMA and NMA indicated that nearly all TCMIs were more efficacious than conventional treatments for angina pectoris. Adequate subgroup and sensitivity analyses found the robust and consistent results. However, the evidence strengths of meta-analyses were assessed as very low to low due to the high risk of RCTs. The comprehensive efficacy estimates suggested that 4 TCMIs (HH, Honghua injection; HHH, Honghua Huangsesu injection; GLP, Gualoupi injection; and SM, Shenmai injection) was the best anti-anginal drugs for adults with angina pectoris.

CONCLUSION

TCMIs appear to be efficacious for angina pectoris, although evidence evaluation of high-quality RCTs of TCMIs would be necessary. In particular, randomization and blinding procedures of the RCTs should be explicated to meet the CONSORT requirements.

Should studies with no events in both arms be excluded in evidence synthesis?

OBJECTIVES

In safety assessment, studies with no events are a frequent occurrence when conducting meta-analyses. The current approach in meta-analysis is to exclude double-zero studies from the synthesis. In this study, we compared the performance of excluding and including double-zero studies.

METHODS

A simulation with 5000 iterations was conducted based on the real-world dataset from Cochrane reviews. The true distribution of the rare events rather than normal distribution for the effects were used in the data generating mechanism to simulate aggregate meta-analysis data. We used Doi's inverse variance heterogeneity (IVhet) model for the meta-analyses with continuity correction (of 0.5) to include double-zero studies and used the odds ratio effect size. The performance of including versus excluding double-zero studies were then compared.

RESULTS

Generally, there was much larger mean squared error when double zero studies were excluded than when double-zero studies were included. The coverage when studies were excluded rapidly deteriorates as heterogeneity increased, while remained at or above the nominal level when double-zero studies were included. When there were very few double-zero studies, the performances was almost the same when including or excluding these studies. Subgroup analysis showed that, even for meta-analyses with unbalanced sample size across the two arms, including double-zero studies improved performance compared to when they were excluded.

CONCLUSIONS

Including double-zero studies in meta-analysis improved performance substantively when compared to excluding them, especially when the proportion of double-zero studies was large. Continuity correction with use of the IVhet model is therefore a good solution to deal with double-zero studies and should be considered in future meta-analyses.

No Difference in Complications Between Elbow Ulnar Collateral Ligament Reconstruction With the Docking and Modified Jobe Techniques: A Systematic Review and Meta-analysis

BACKGROUND

The most commonly used techniques for elbow ulnar collateral ligament reconstruction (UCLR) are the docking and modified Jobe figure-of-8 techniques. Previous literature has suggested that UCLR with the docking technique is associated with fewer complications; however, these studies included results from the original classic Jobe technique without controlling for the effects of flexor pronator mass (FPM) detachment and routine submuscular ulnar nerve transposition (UNT).

PURPOSE/HYPOTHESIS

This study sought to compare the rates of complications and subsequent unplanned surgical procedures between the docking and figure-of-8 techniques. We hypothesized that there would be no significant difference in the rates of complications or subsequent unplanned surgical procedures between the techniques when the FPM was preserved and no routine submuscular UNT was performed.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A series of mixed-effects multivariate metaregression models were implemented using the restricted maximum likelihood method. Complications and subsequent unplanned surgical procedures were modeled as Freeman-Tukey transformed incidence rates for variance stabilization, and nerve-specific complications were assessed as the Freeman-Tukey transformed proportion of cases, with back-transformation to estimate summary effects.

RESULTS

There were 19 studies eligible for qualitative analysis, consisting of 1788 cases of UCLR (303 docking, 1485 figure-of-8), 18 of which were suitable for quantitative analysis (1769 cases; 291 docking, 1478 figure-of-8). A total of 338 complications were reported (17 for docking, 321 for figure-of-8), the majority of which were nerve related. Additionally, a total of 75 subsequent unplanned surgical procedures were related to the index UCLR procedure. There was no significant difference in the rate of complications (P = .146) or proportion of cases with nerve-specific complications (P = .127) between the docking and figure-of-8 techniques when controlling for FPM preservation versus detachment with submuscular UNT. FPM detachment with submuscular UNT was independently associated with a significantly higher proportion of postoperative nerve-related complications (P = .004). There was also no significant difference in the rates of subsequent unplanned surgical procedures between the docking and figure-of-8 techniques (P = .961), although FPM detachment with routine submuscular UNT was independently associated with a significantly higher incidence of subsequent unplanned surgical procedures.

CONCLUSION

The results of this study demonstrate no significant difference in the rates of complications or subsequent unplanned surgical procedures between the figure-of-8 and docking techniques for UCLR when controlling for FPM preservation versus detachment with submuscular UNT. With modern muscle-sparing approaches and avoiding submuscular UNT, the modified Jobe technique does not differ significantly from the docking technique in terms of complication rates, proportions of cases with nerve-specific complications, or rates of subsequent unplanned surgical procedures.

The Cooperation Databank: Machine-Readable Science Accelerates Research Synthesis

Publishing studies using standardized, machine-readable formats will enable machines to perform meta-analyses on demand. To build a semantically enhanced technology that embodies these functions, we developed the Cooperation Databank (CoDa)—a databank that contains 2,636 studies on human cooperation (1958–2017) conducted in 78 societies involving 356,283 participants. Experts annotated these studies along 312 variables, including the quantitative results (13,959 effects). We designed an ontology that defines and relates concepts in cooperation research and that can represent the relationships between results of correlational and experimental studies. We have created a research platform that, given the data set, enables users to retrieve studies that test the relation of variables with cooperation, visualize these study results, and perform (a) meta-analyses, (b) metaregressions, (c) estimates of publication bias, and (d) statistical power analyses for future studies. We leveraged the data set with visualization tools that allow users to explore the ontology of concepts in cooperation research and to plot a citation network of the history of studies. CoDa offers a vision of how publishing studies in a machine-readable format can establish institutions and tools that improve scientific practices and knowledge.

Of differing methods, disputed estimates and discordant interpretations: the meta-analytical multiverse of brain volume and IQ associations

Brain size and IQ are positively correlated. However, multiple meta-analyses have led to considerable differences in summary effect estimations, thus failing to provide a plausible effect estimate. Here we aim at resolving this issue by providing the largest meta-analysis and systematic review so far of the brain volume and IQ association (86 studies; 454 effect sizes from k = 194 independent samples; N = 26 000+) in three cognitive ability domains (full-scale, verbal, performance IQ). By means of competing meta-analytical approaches as well as combinatorial and specification curve analyses, we show that most reasonable estimates for the brain size and IQ link yield r-values in the mid-0.20s, with the most extreme specifications yielding rs of 0.10 and 0.37. Summary effects appeared to be somewhat inflated due to selective reporting, and cross-temporally decreasing effect sizes indicated a confounding decline effect, with three quarters of the summary effect estimations according to any reasonable specification not exceeding r = 0.26, thus contrasting effect sizes were observed in some prior related, but individual, meta-analytical specifications. Brain size and IQ associations yielded r = 0.24, with the strongest effects observed for more g-loaded tests and in healthy samples that generalize across participant sex and age bands.

Association between SARS-Cov-2 infection during pregnancy and adverse pregnancy outcomes: a re-analysis of the data reported by Wei et al. (2021)

Objectives and background

Wei et al. have published a meta-analysis (MA), which aimed to evaluate the association between SARS-CoV-2 infection during pregnancy and adverse pregnancy outcomes. Using classical random-effects model, they found that SARS-CoV-2 infection was associated with preeclampsia, preterm birth and stillbirth. Performing MA with low event rates or with few studies may be challenging insofar as MA relies on several within and between-study distributional assumptions. The objective was to assess the robustness of the results provided by Wei et al.

Methods

We performed a sensitivity analysis using frequentist and Bayesian meta-analysis methods. We also estimated fragility indexes.

Results

For eclampsia, the confidence intervals of most frequentist models contain 1. All beta-binomial models (Bayesian) lead to credible intervals containing 1. The prediction interval, based on DL method, ranges from 0.75 to 2.38. The fragility index is 2 for the DL method. For preterm, the confidence (credible) intervals exclude 1. The prediction interval is broad, ranging from 0.84 to 20.61. The fragility index ranges from 27 to 10. For stillbirth, the confidence intervals of most frequentist models contain 1. Six Bayesian MA models lead to credible intervals containing 1. The prediction interval ranges from 0.52 to 8.49. The fragility index is 3.

Conclusion

Given the available data and the results of our broad sensitivity analysis, we can suggest that SARS-CoV-2 infection during pregnancy is associated with preterm, and that it may be associated with preeclampsia. For stillbirth, more data are needed as none of the Bayesian analyses are conclusive.

A penalization approach to random-effects meta-analysis

Systematic reviews and meta-analyses are principal tools to synthesize evidence from multiple independent sources in many research fields. The assessment of heterogeneity among collected studies is a critical step when performing a meta-analysis, given its influence on model selection and conclusions about treatment effects. A common-effect (CE) model is conventionally used when the studies are deemed homogeneous, while a random-effects (RE) model is used for heterogeneous studies. However, both models have limitations. For example, the CE model produces excessively conservative confidence intervals with low coverage probabilities when the collected studies have heterogeneous treatment effects. The RE model, on the other hand, assigns higher weights to small studies compared to the CE model. In the presence of small-study effects or publication bias, the over-weighted small studies from a RE model can lead to substantially biased overall treatment effect estimates. In addition, outlying studies may exaggerate between-study heterogeneity. This article introduces penalization methods as a compromise between the CE and RE models. The proposed methods are motivated by the penalized likelihood approach, which is widely used in the current literature to control model complexity and reduce variances of parameter estimates. We compare the existing and proposed methods with simulated data and several case studies to illustrate the benefits of the penalization methods.

Transcriptome analysis of childhood Guillain-Barré syndrome associated with supportive care

Childhood Guillain-Barré syndrome (GBS) is a rare neurological disease. Early diagnosis followed by precise treatment can reduce mortality. In this study, we collected two transcriptome data between GBS and controls from the publicly available databases (GEO dataset). We identified two distinct down-regulated genes (PTGDS and AR) in GBS by transcriptome analysis (n = 20). Based on the two distinct down-regulated genes in the GBS group, a two-gene diagnostic signature was developed. Moreover, gene expression analysis for the two-gene was performed on a patient with GBS before and after Supportive Care. RT-PCR results show that the expression of PTGDS increased after the patient was given supportive care. Therefore, PTGDS might be considered as a potential target for therapeutic target in GBS.

Retrospective median power, false positive meta-analysis and large-scale replication

Recent, high-profile, large-scale, preregistered failures to replicate uncover that many highly-regarded experiments are "false positives"; that is, statistically significant results of underlying null effects. Large surveys of research reveal that statistical power is often low and inadequate. When the research record includes selective reporting, publication bias and/or questionable research practices, conventional meta-analyses are also likely to be falsely positive. At the core of research credibility lies the relation of statistical power to the rate of false positives. This study finds that high (>50%-60%) median retrospective power (MRP) is associated with credible meta-analysis and large-scale, preregistered, multi-lab "successful" replications; that is, with replications that corroborate the effect in question. When median retrospective power is low (<50%), positive meta-analysis findings should be interpreted with great caution or discounted altogether.

Preferred reporting items for systematic reviews and meta-analyses in ecology and evolutionary biology: a PRISMA extension

Since the early 1990s, ecologists and evolutionary biologists have aggregated primary research using meta-analytic methods to understand ecological and evolutionary phenomena. Meta-analyses can resolve long-standing disputes, dispel spurious claims, and generate new research questions. At their worst, however, meta-analysis publications are wolves in sheep's clothing: subjective with biased conclusions, hidden under coats of objective authority. Conclusions can be rendered unreliable by inappropriate statistical methods, problems with the methods used to select primary research, or problems within the primary research itself. Because of these risks, meta-analyses are increasingly conducted as part of systematic reviews, which use structured, transparent, and reproducible methods to collate and summarise evidence. For readers to determine whether the conclusions from a systematic review or meta-analysis should be trusted - and to be able to build upon the review - authors need to report what they did, why they did it, and what they found. Complete, transparent, and reproducible reporting is measured by 'reporting quality'. To assess perceptions and standards of reporting quality of systematic reviews and meta-analyses published in ecology and evolutionary biology, we surveyed 208 researchers with relevant experience (as authors, reviewers, or editors), and conducted detailed evaluations of 102 systematic review and meta-analysis papers published between 2010 and 2019. Reporting quality was far below optimal and approximately normally distributed. Measured reporting quality was lower than what the community perceived, particularly for the systematic review methods required to measure trustworthiness. The minority of assessed papers that referenced a guideline (~16%) showed substantially higher reporting quality than average, and surveyed researchers showed interest in using a reporting guideline to improve reporting quality. The leading guideline for improving reporting quality of systematic reviews is the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement. Here we unveil an extension of PRISMA to serve the meta-analysis community in ecology and evolutionary biology: PRISMA-EcoEvo (version 1.0). PRISMA-EcoEvo is a checklist of 27 main items that, when applicable, should be reported in systematic review and meta-analysis publications summarising primary research in ecology and evolutionary biology. In this explanation and elaboration document, we provide guidance for authors, reviewers, and editors, with explanations for each item on the checklist, including supplementary examples from published papers. Authors can consult this PRISMA-EcoEvo guideline both in the planning and writing stages of a systematic review and meta-analysis, to increase reporting quality of submitted manuscripts. Reviewers and editors can use the checklist to assess reporting quality in the manuscripts they review. Overall, PRISMA-EcoEvo is a resource for the ecology and evolutionary biology community to facilitate transparent and comprehensively reported systematic reviews and meta-analyses.

Action and Inaction in Moral Judgments and Decisions: Meta-Analysis of Omission Bias Omission-Commission Asymmetries

Omission bias is people's tendency to evaluate harm done through omission as less morally wrong and less blameworthy than commission when there is harm. However, findings are inconsistent. We conducted a preregistered meta-analysis, with 21 samples (13 articles, 49 effects) on omission-commission asymmetries in judgments and decisions. We found an overall effect of g = 0.45, 95% confidence interval (CI) = [0.14, 0.77], with stronger effects for morality and blame than for decisions. Publication bias tests produced mixed results with some indication for publication bias, though effects persisted even after most publication bias adjustments. The small sample of studies included limited our ability to draw definite conclusions regarding moderators, with inconclusive findings when applying different models. After compensating for low power, we found indication for moderation by role responsibility, perspective (self vs. others), outcome type, and study design. We hope this meta-analysis will inspire research on this phenomenon and applications to real-life, especially given the raging pandemic. Materials, data, and code are available on https://osf.io/9fcqm/.

Examining how meta-analytic methods perform in the presence of bias: A simulation study

Standard meta-analysis methods are vulnerable to bias from incomplete reporting of results (both publication and outcome reporting bias) and poor study quality. Several alternative methods have been proposed as being less vulnerable to such biases. To evaluate these claims independently we simulated study results under a broad range of conditions first with no bias, then introducing simulated publication bias, outcome reporting bias, and bias from poor study quality. We then implemented common and the proposed bias robust meta-analysis methods and compared the mean bias and mean squared error (MSE) for four estimates of effect and the coverage probability of seven confidence intervals. We found that no methods perform well in the presence of any substantial bias. A regression based extension to Egger's test gave an estimate of effect with lower mean bias than standard methods in the presence of publication bias or poor study quality, but had a substantially worse MSE except in very specific conditions. Coverage of all 95% confidence intervals was very poor with increasing numbers of studies in biased conditions, often falling below 50%. The Knapp-Hartung interval performed closest to nominal coverage with fewer than 10 studies in most conditions, and the Henmi-Copas interval generally performed best with more than 10 studies. There was no evidence that a multiplicative term for heterogeneity improved coverage. Multiple forms of bias remain problematic for all meta-analysis methods, with very poor performance under conceivable conditions.

Comparison of Balloon Guide Catheters and Standard Guide Catheters for Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Balloon guide catheters (BGCs) are designed to induce flow arrest during mechanical thrombectomy procedures for acute ischemic stroke due to large-vessel occlusion and have been associated with improved clinical and angiographic outcomes. We conducted a systematic review and meta-analysis evaluating the relative technical and clinical outcomes associated with BGC versus non-BGC approaches.

METHODS

A systematic review of clinical literature using the PubMed database was undertaken to identify multiarm studies published between 2010 and 2021 reporting the use of BGC versus non-BGC approaches for stroke treatment. Data collected included complete recanalization (thrombolysis in cerebral infarction, TICI), first-pass effect TICI 3, puncture-to recanalization time, number of endovascular attempts, distal embolization, symptomatic intracerebral hemorrhage, 90-day modified Rankin Scale score 0-2, and 90-day mortality. Subgroup analyses assessed the impact of treatment device (stent-retrievers, contact aspiration, combination therapy, and not specified/other). A random effects model was fit for each outcome measure.

RESULTS

Fifteen studies were included. Compared with non-BGC approaches, patients treated with BGCs had greater odds of TICI 3 (odds ratio [OR] 1.57; 95% confidence interval [95% CI] 1.08-2.29) and first-pass effect TICI 3 (OR 3.63; 95% CI 2.34-5.62), reduced puncture-to-revascularization time (mean difference -7.8; 95% CI -13.3 to -2.2), fewer endovascular attempts (mean difference -0.47; 95% CI -0.68 to -0.26), reduced odds of distal emboli (OR 0.34; 95% CI 0.17-0.71) and symptomatic intracerebral hemorrhage (OR 0.66; 95% CI 0.51-0.86), greater odds of 90-day modified Rankin Scale score 0-2 (OR 1.51; 95% CI 1.27-1.79), and reduced odds of mortality (OR 0.69; 95% CI 0.57-0.82).

CONCLUSIONS

BGCs yield superior technical and clinical outcomes while reducing patient complications.

Exploring consequences of simulation design for apparent performance of methods of meta-analysis

Contemporary statistical publications rely on simulation to evaluate performance of new methods and compare them with established methods. In the context of random-effects meta-analysis of log-odds-ratios, we investigate how choices in generating data affect such conclusions. The choices we study include the overall log-odds-ratio, the distribution of probabilities in the control arm, and the distribution of study-level sample sizes. We retain the customary normal distribution of study-level effects. To examine the impact of the components of simulations, we assess the performance of the best available inverse-variance-weighted two-stage method, a two-stage method with constant sample-size-based weights, and two generalized linear mixed models. The results show no important differences between fixed and random sample sizes. In contrast, we found differences among data-generation models in estimation of heterogeneity variance and overall log-odds-ratio. This sensitivity to design poses challenges for use of simulation in choosing methods of meta-analysis.

Corticosteroid therapy for COVID-19: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Corticosteroid treatment is an effective and common therapeutic strategy for various inflammatory lung pathologies and may be an effective treatment for coronavirus disease 2019 (COVID-19). The purpose of this systematic review and meta-analysis of current literature was to investigate the clinical outcomes associated with corticosteroid treatment of COVID-19.

METHODS

We systematically searched PubMed, medRxiv, Web of Science, and Scopus databases through March 10, 2021 to identify randomized controlled trials (RCTs) that evaluated the effects of corticosteroid therapies for COVID-19 treatment. Outcomes of interest were mortality, need for mechanical ventilation, serious adverse events (SAEs), and superinfection.

RESULTS

A total of 7737 patients from 8 RCTs were included in the quantitative meta-analysis, of which 2795 (36.1%) patients received corticosteroids plus standard of care (SOC) while 4942 (63.9%) patients received placebo and/or SOC alone. The odds of mortality were significantly lower in patients that received corticosteroids as compared to SOC (odds ratio [OR] = 0.85 [95% CI: 0.76; 0.95], P = .003). Corticosteroid treatment reduced the odds of a need for mechanical ventilation as compared to SOC (OR = 0.76 [95% CI: 0.59; 0.97], P = .030). There was no significant difference between the corticosteroid and SOC groups with regards to SAEs and superinfections.

CONCLUSION

Corticosteroid treatment can reduce the odds for mortality and the need for mechanical ventilation in severe COVID-19 patients.

Clinical Hypnosis as an Adjunct to Cognitive Behavior Therapy: An Updated Meta-Analysis

In 1995, Kirsch and colleagues published an influential meta-analysis (k = 20, N = 577) which found that CBT enhanced with hypnosis (CBTH) was superior to CBT alone by at least d = .53. However, a lack of full replication and the emergence of new empirical studies prompted this updated analysis. A total of 48 post- (N = 1,928) and 25 follow-up treatments (N = 1,165) were meta-analyzed. CBTH achieved small to medium but statistically significant advantages over CBT at posttreatment (d_IGPP/d = .25 to .41), and specifically in the management of depressed mood and pain. At follow-up, there was a medium sized advantage for CBTH (d_IGPP/d = .54 to .59), and specifically for the treatment of obesity. These results further support the adjunctive use of hypnosis as an enhancer of CBT's efficaciousness and endurance as a treatment.

A confidence interval robust to publication bias for random-effects meta-analysis of few studies

In meta-analyses including only few studies, the estimation of the between-study heterogeneity is challenging. Furthermore, the assessment of publication bias is difficult as standard methods such as visual inspection or formal hypothesis tests in funnel plots do not provide adequate guidance. Previously, Henmi and Copas (Statistics in Medicine 2010, 29: 2969-2983) proposed a confidence interval for the overall effect in random-effects meta-analysis that is robust to publication bias to some extent. As is evident from their simulations, the confidence intervals have improved coverage compared with standard methods. To our knowledge, the properties of their method have never been assessed for meta-analyses including fewer than five studies. In this manuscript, we propose a variation of the method by Henmi and Copas employing an improved estimator of the between-study heterogeneity, in particular when dealing with few studies only. In a simulation study, the proposed method is compared to several competitors. Overall, we found that our method outperforms the others in terms of coverage probabilities.

Efficacy of convalescent plasma therapy for COVID-19: A systematic review and meta-analysis

The purpose of this systematic review and meta‐analysis was to examine clinical outcomes associated with convalescent plasma therapy in COVID‐19 patients. We performed a literature search on PubMed, medRxiv, Web of Science, and Scopus to identify studies published up to December 10th, 2020 that examined the efficacy of convalescent plasma treatment for COVID‐19. The primary endpoints were mortality, clinical improvement, and hospital length of stay. We screened 859 studies that met the search criteria, performed full‐text reviews of 56 articles, and identified 15 articles that fulfilled inclusion criteria for meta‐analysis. The odds of mortality were significantly lower in the convalescent plasma group compared to the control group (OR = 0.59 [95% CI = 0.44; 0.78], P < .001), although results from two key randomized controlled trials did not support the mortality benefit. The odds of clinical improvement were significantly higher in the convalescent plasma group compared to the control group (OR = 2.02 [95% CI = 1.54; 2.65], P < .001). There was no difference in hospital length of stay between the convalescent plasma group and the control group (MD = −0.49 days [95% CI = −3.11; 2.12], P = .713). In all, these data indicate that a mortality benefit with convalescent plasma is unclear, although there remain benefits with convalescent plasma therapy for COVID‐19.

Evaluation of various estimators for standardized mean difference in meta-analysis

Meta-analyses of a treatment's effect compared with a control frequently calculate the meta-effect from standardized mean differences (SMDs). SMDs are usually estimated by Cohen's d or Hedges' g. Cohen's d divides the difference between sample means of a continuous response by the pooled standard deviation, but is subject to nonnegligible bias for small sample sizes. Hedges' g removes this bias with a correction factor. The current literature (including meta-analysis books and software packages) is confusingly inconsistent about methods for synthesizing SMDs, potentially making reproducibility a problem. Using conventional methods, the variance estimate of SMD is associated with the point estimate of SMD, so Hedges' g is not guaranteed to be unbiased in meta-analyses. This article comprehensively reviews and evaluates available methods for synthesizing SMDs. Their performance is compared using extensive simulation studies and analyses of actual datasets. We find that because of the intrinsic association between point estimates and standard errors, the usual version of Hedges' g can result in more biased meta-estimation than Cohen's d. We recommend using average-adjusted variance estimators to obtain an unbiased meta-estimate, and the Hartung-Knapp-Sidik-Jonkman method for accurate estimation of its confidence interval.

A unified method for improved inference in random effects meta-analysis

Random effects meta-analyses have been widely applied in evidence synthesis for various types of medical studies. However, standard inference methods (e.g. restricted maximum likelihood estimation) usually underestimate statistical errors and possibly provide highly overconfident results under realistic situations; for instance, coverage probabilities of confidence intervals can be substantially below the nominal level. The main reason is that these inference methods rely on large sample approximations even though the number of synthesized studies is usually small or moderate in practice. In this article, we solve this problem using a unified inference method based on Monte Carlo conditioning for broad application to random effects meta-analysis. The developed method provides improved confidence intervals with coverage probabilities that are closer to the nominal level than standard methods. As specific applications, we provide new inference procedures for three types of meta-analysis: conventional univariate meta-analysis for pairwise treatment comparisons, meta-analysis of diagnostic test accuracy, and multiple treatment comparisons via network meta-analysis. We also illustrate the practical effectiveness of these methods via real data applications and simulation studies.

Modified Jobe Versus Docking Technique for Elbow Ulnar Collateral Ligament Reconstruction: A Systematic Review and Meta-analysis of Clinical Outcomes

BACKGROUND

The modified Jobe and docking techniques are the most common techniques used for elbow ulnar collateral ligament (UCL) reconstruction. Previous systematic reviews have suggested that the docking technique results in superior outcomes as compared with the Jobe (figure-of-8) technique. However, these included results from earlier studies in which the flexor-pronator mass (FPM) was detached and an obligatory submuscular ulnar nerve transposition was performed.

PURPOSE/HYPOTHESIS

The purpose was to compare the outcomes and return-to-play (RTP) time between the docking and figure-of-8 techniques for UCL reconstruction. We hypothesized that there would be no significant difference in the proportion of excellent outcomes between techniques when the FPM was preserved and no obligatory submuscular ulnar nerve transposition was performed. We also hypothesized that there would be no significant difference in RTP time between techniques.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. In the primary analysis, techniques were compared in random effects models by using the restricted maximum likelihood method, with weighted effect sizes calculated as the Freeman-Tukey double-arcsine transformed proportion of excellent outcomes for variance stabilization and with summary effects estimated from the inverse double-arcsine transformation per the harmonic mean of the sample sizes. Mean RTP times for techniques were compared in a separate model.

RESULTS

There were 21 eligible articles identified, with results for 1842 UCL reconstructions (n = 320, docking; n = 1466, figure-of-8). Without controlling for the effects of flexor-pronator detachment and submuscular ulnar nerve transposition, a significantly larger proportion of excellent outcomes was observed with docking reconstruction (86.58%; 95% CI, 80.42%-91.85%) than with figure-of-8 reconstruction (76.76%; 95% CI, 69.65%-83.25%; P = .031); however, there was no significant difference between techniques when controlling for FPM preservation or detachment with submuscular nerve transposition (P = .139). There was no significant difference between techniques in time to return to sports (P = .729), although no reconstructions with FPM detachment and submuscular ulnar nerve transposition were available for RTP time analysis.

CONCLUSION

There was no significant difference in the proportion of excellent Conway Scale outcomes or RTP time between the docking and modified Jobe techniques for UCL reconstruction when the FPM was preserved and routine submuscular ulnar nerve transposition was not performed.

Interval estimation of the overall treatment effect in random-effects meta-analyses: Recommendations from a simulation study comparing frequentist, Bayesian, and bootstrap methods

There exists a variety of interval estimators for the overall treatment effect in a random-effects meta-analysis. A recent literature review summarizing existing methods suggested that in most situations, the Hartung-Knapp/Sidik-Jonkman (HKSJ) method was preferable. However, a quantitative comparison of those methods in a common simulation study is still lacking. Thus, we conduct such a simulation study for continuous and binary outcomes, focusing on the medical field for application. Based on the literature review and some new theoretical considerations, a practicable number of interval estimators is selected for this comparison: the classical normal-approximation interval using the DerSimonian-Laird heterogeneity estimator, the HKSJ interval using either the Paule-Mandel or the Sidik-Jonkman heterogeneity estimator, the Skovgaard higher-order profile likelihood interval, a parametric bootstrap interval, and a Bayesian interval using different priors. We evaluate the performance measures (coverage and interval length) at specific points in the parameter space, that is, not averaging over a prior distribution. In this sense, our study is conducted from a frequentist point of view. We confirm the main finding of the literature review, the general recommendation of the HKSJ method (here with the Sidik-Jonkman heterogeneity estimator). For meta-analyses including only two studies, the high length of the HKSJ interval limits its practical usage. In this case, the Bayesian interval using a weakly informative prior for the heterogeneity may help. Our recommendations are illustrated using a real-world meta-analysis dealing with the efficacy of an intramyocardial bone marrow stem cell transplantation during coronary artery bypass grafting.

Cognitive and academic benefits of music training with children: A multilevel meta-analysis

Music training has repeatedly been claimed to positively impact children's cognitive skills and academic achievement (literacy and mathematics). This claim relies on the assumption that engaging in intellectually demanding activities fosters particular domain-general cognitive skills, or even general intelligence. The present meta-analytic review (N = 6,984, k = 254, m = 54) shows that this belief is incorrect. Once the quality of study design is controlled for, the overall effect of music training programs is null ([Formula: see text] ≈ 0) and highly consistent across studies (τ2 ≈ 0). Results of Bayesian analyses employing distributional assumptions (informative priors) derived from previous research in cognitive training corroborate these conclusions. Small statistically significant overall effects are obtained only in those studies implementing no random allocation of participants and employing non-active controls ([Formula: see text] ≈ 0.200, p < .001). Interestingly, music training is ineffective regardless of the type of outcome measure (e.g., verbal, non-verbal, speed-related, etc.), participants' age, and duration of training. Furthermore, we note that, beyond meta-analysis of experimental studies, a considerable amount of cross-sectional evidence indicates that engagement in music has no impact on people's non-music cognitive skills or academic achievement. We conclude that researchers' optimism about the benefits of music training is empirically unjustified and stems from misinterpretation of the empirical data and, possibly, confirmation bias.

The effect of perceived threat on human rights: A meta-analysis

Individuals express support for civil liberties and human rights, but when threatened tend to restrict rights for both others and themselves. However, the question of whether or not rights are restricted to punish others or protect ourselves remains unclear. This meta-analysis integrates the findings of the effect of perceived threats on support for restrictions of civil liberties from 1997 to 2019. It includes 163 effect-size estimates from 46 different articles involving 91,716 participants. The presence of threat increased support for restrictions against outgroup members significantly more than ingroup members, providing a possible punitive explanation for support for restrictions of civil liberties. These findings contribute to the debate on rights and their relationship with deservingness, suggesting that we delineate those who deserve human rights and those who do not.

Impact of past behaviour normality: meta-analysis of exceptionality effect

Exceptionality effect is the phenomenon that people associate stronger negative affect with a negative outcome when it is a result of an exception (abnormal behaviour) compared to when it is a result of routine (normal behaviour). In this pre-registered meta-analysis, we examined exceptionality effect in 48 studies (N = 4212). An analysis of 35 experimental studies (n = 3332) showed medium to strong effect (g = 0.60, 95% confidence intervals (CI) [0.41, 0.79]) for past behaviour across several measures (regret/affect: g = 0.66, counterfactual thought: g = 0.39, self-blame: g = 0.44, victim compensation: g = 0.39, offender punishment: g = 0.51). An analysis of 13 one-sample studies presenting a comparison of exceptional and routine behaviours simultaneously (n = 1217) revealed a very strong exceptionality effect (converted g = 1.98, CI [1.57, 2.38]). We tested several theoretical moderators: norm strength, event controllability, outcome rarity, action versus inaction, and status quo. We found that exceptionality effect was stronger when the routine was aligned with the status quo option and with action rather than for inaction. All materials are available on: https://osf.io/542c7/.

Psychological interventions using virtual reality for pain associated with medical procedures: a systematic review and meta-analysis

BACKGROUND

Virtual reality (VR) may enhance the effectiveness of psychological interventions for acute pain. We conducted a meta-analysis to assess the efficacy and safety of VR-based interventions for pain associated with medical procedures.

METHODS

We searched PubMed, EMBASE, the Cochrane Library, and PsycINFO until June 17th 2018. We identified randomized controlled trials (RCTs), comparing VR-based psychological interventions to usual care, for pain intensity (primary outcome) or affective and cognitive components of pain (secondary outcomes), assessed real-time or retrospectively. Two independent reviewers performed study selection and data extraction. Risk of bias was independently evaluated by three raters using the revised Cochrane Collaboration tool. A random-effects model using the Paule and Mandel estimator was used for pooling effect sizes.

RESULTS

27 RCTs (1452 patients) provided enough data for meta-analysis. Compared to usual care, VR-based interventions reduced pain intensity both real-time (9 RCTs, Hedges' g = 0.95, 95% CI 0.32-1.57) and retrospectively (22 RCTs, g = 0.87, 95% CI 0.54-1.21). Results were similar for cognitive (8 RCTs, g = 0.82, 95% CI 0.39-1.26) and affective pain components (14 RCTs, g = 0.55, 95% CI 0.34-0.77). There was marked heterogeneity, which remained similarly high in sensitivity analyses. Across domains, few trials were rated as low risk of bias and there was evidence of publication bias. Adverse events were rare.

CONCLUSIONS

Though VR-based interventions reduced pain for patients undergoing medical procedures, inferring clinical effectiveness is precluded by the predominance of small trials, with substantial risk of bias, and by incomplete reporting.

A Meta-Analysis of Neuropsychological Predictors of Outcome Following Stroke and Other Non-Traumatic Acquired Brain Injuries in Adults

A number of cognitive abilities have been reported to predict outcome following a non-traumatic acquired brain injury (ABI) in adults. However, the results are inconsistent. Furthermore, the unique and combined capacity of these cognitive abilities to predict ABI outcome has not been evaluated. Consequently, we employed meta-analysis and multiple regression to evaluate the capacity of various neuropsychological domains to predict two separate outcome variables in adults: (1) activities of daily living; and (2) quality of life. Based on the activities of daily living meta-analysis (N = 2384), we estimated the following significant bivariate effects: memory (r = .31, 95% CI: .20/.41]), language (r = .33, 95% CI:.26/.40), attention (r = .38, 95% CI: .30/.46]), executive functions (r = .29, 95% CI: .19/.39]), and visuospatial abilities (r = .41, 95% CI: .34/ .48). Based on the quality of life meta-analysis (N = 1037), we estimated the following significant bivariate effects: memory (r = .12, 95% CI: .03/.20]), language (r = .19, 95% CI: .06/ .32), attention (r = .30, 95% CI: .16/.44]), executive functions (r = .24, 95% CI: .12/.37) and visuospatial/constructional abilities (r = .30, 95% CI: .14/.46). Meta-analytic structural equation modelling (metaSEM) identified two significant, unique predictors of activities of daily living, attention and visuospatial abilities, and the model accounted for 21% of the variance (multiple R² = .21, 95%CI: .16/.26). For the corresponding quality of life metaSEM, no statistically significant unique predictors were identified, however, a significant multiple correlation was observed, multiple R² = .11 (95%CI: 04/.18). We conclude that practitioners may be able to predict, with some degree of accuracy, functional outcome following a stroke and other non-traumatic ABI in adults. We also provide some critical commentary on the nature and quality of the measures used in this area of research to represent the cognitive dimensions of interest.

Can intensity in strength training change caloric expenditure? Systematic review and meta-analysis

INTRODUCTION

Strength training (ST) is considered an important strategy for maintaining body weight, as it promotes an increase in total energy expenditure (EE). However, the combination and manipulation of variables (intensity and volume) allow for different training adaptations. However, it remains unclear as to what is the most important variable between volume or intensity for example number of sets, repetitions, or total load for maximizing EE during ST. Several studies have analyzed the EE response in ST, but still unclear the variable is able to increase EE in the ST.

OBJECTIVE

This review aimed to investigate the effect of ST on EE in adults using a systematic literature review and subsequent meta-analysis.

METHODS

The search was performed on the electronic databases using the following keywords: strength training (resistance training; strength training; strength training method) and energy expenditure (energy metabolism; energy expenditure; caloric expenditure, caloric cost) with 'AND' and 'OR' combination. Manual searches of references were also conducted for additional relevant studies. After evaluating the inclusion and exclusion criteria, the selected studies were analysed according to strength training methods and the training variables used to measure EE.

RESULTS

We identified two ST methods from the literature review: circuit training (CT) and traditional training (TT). Meta-analysis showed a significant effect on EE increase, which favour TT when compared with CT [-0·99 (95%CI: -1·96, -0·02), P<0·01] with I² of 89% (P<0·01). After adjusting for bias risk, no significant differences were found in EE associated with intensity [-0·40, 95% CI (0·98, 0·18), P = 0·18).

CONCLUSION

The present review and meta-analysis indicated that the intensity of exercise does not seem to be associated with an increase of EE in ST.

Effects of Physical Activity on the Physical and Psychosocial Health of Youth With Intellectual Disabilities: A Systematic Review and Meta-Analysis

BACKGROUND

The physical and psychosocial benefits of physical activity for typically developing youth are well established; however, its impact on youth with intellectual disabilities is not as well understood. The aims of this review and meta-analysis were to synthesize the literature and quantify the effects of physical activity on the physical and psychosocial health of youth with intellectual disabilities.

METHOD

Studies meeting the inclusion criteria were grouped by their focus on physical health and/or psychosocial health outcomes. Meta-analyses were performed using 3-level, random effects and mixed effects models.

RESULTS

One hundred nine studies met the inclusion criteria. Physical activity had a large effect on physical health (g = 0.773, P < .001) and a moderately large effect (g = 0.682, P < .001) on psychosocial health. Participant age, intellectual disability level, other developmental disabilities, outcome type, and intervention type moderated the effects of physical activity on physical health, whereas study design, risk of bias, other developmental disabilities, outcome type, and intervention type were moderators on psychosocial health.

CONCLUSIONS

Physical activity has positive effects on the physical and psychosocial health of youth with intellectual disabilities. Although resistance training shows the most physical benefits, teaching movement and sports skills appear to benefit their physical and psychosocial health.

Setting Doesn’t Matter Much

Abstract. This study deals with the effects of the diagnostic setting on the performance in intelligence tests. We conducted a meta-analysis in which k = 30 samples with a total sample size of N = 2,448 were integrated. We compared results for the same intelligence tests administered either in a group or in an individual setting. The main analysis indicated a small mean population effect [ M( g) = 0.085] that was not significant [−0.036 ≤  M( g) ≤ 0.206]. Nevertheless, moderator analyses indicated a stronger [ M( g) = 0.193] and significant [0.087 ≤  M( g) ≤ 0.298] effect in favor of individual settings for studies employing a between-person design. Setting effects in within-person designs were most likely superimposed by retest effects. As the setting effect was very small, the current testing practice in which results obtained in group and individual settings are treated as interchangeable is not overly problematic. However, our results encourage test developers to examine setting effects before stating that results obtained in different settings are equivalent. Between-person designs using participants of comparable ability are most suitable in this context as retest effects can be ruled out.