Questions tagged [meta-analysis]

Methods focused on contrasting and combining results from different studies, in the hope of increasing precision and external validity.

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1answer
401 views

Meta-analysis: How can I compute the sampling variance of Fisher's z-transformed correlation coefficients for within-subject designs?

Rosenthal and colleagues (Rosenthal, Rosnow & Rubin, 2000) suggest that it is possible to compute r (correlation coefficient) as an effect size from repeated measures designs (e.g., by converting ...
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1answer
364 views

Meta-Analysis using RVE (robumeta)

I'm runnig a meta-analysis, correcting for clustering of standard errors with the robumeta command. R gives the following warning: If df < 4, do not trust ...
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13 views

Meta - Analysis - Effect size calculation

I am trying to include a study into my meta-analysis, that reports results of an ANOVA: F(1,76) = 11.23, p = 0.001, n²=0,13 My question is how to calculate Hedge g from this data? I work with R, using ...
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0answers
14 views

Fixed vs. Random effects meta- regression

how to understand the differences between fixed vs. random effects meta-regression? Not meta-analysis.
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1answer
183 views

Reversing the reference category

I am doing a meta-analysis. How can I change the reference category such as in a pooled analysis? Most studies have reported male as the reference group (Female : Male). However in one study the ...
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1answer
350 views

Do I really need correlation coefficients when computing effect sizes from pretest-posttest studies?

I am computing effect sizes from various studies for a meta-analysis. Most of those studies follow a typical pretest-posttest design (repeated measures), thus I compute the effect size as a "...
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2answers
2k views

How do I convert $\eta^2$ to Pearson's r?

I am doing a meta-analysis of associations between sets of variables that are essentially all continuous. However, many studies operationalised them at 'lower' levels, and I have (converted to) most ...
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0answers
38 views

Effect size for meta-analysis from ANOVA with significant interaction term

For a meta-analysis, I found a study in which the main effect of A on my dependant variable was not significant but the interaction of A and B and the interaction of A, B and C were. I also have only ...
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1answer
26 views

Calculating SMD from posttest only - is this possible?

I am performing a meta-analysis (with 'metafor' R-project) as described by Becker (1988), and I compute the standardized mean change for a treatment and control group. I compute a (standardized) ...
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1answer
167 views

Cohens d from Mixed method model - for the interaction term

I am doing a mixed method model: m1 <- lmer(DV ~ IV*Country + (1+IV:Country|Region), data = data) I am using the lme.dscore to get the Cohen's d for the model....
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1answer
41 views

Pooled analysis of studies with only intervention arm

I want to perform a pooled analysis of studies including only a treatment arm, so no proper control groups are available. Studies present data about subjects before the treatment and after treatment, ...
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8 views

Pooled Analysis of studies with only intervention arm: how to do it?

I want to perform a pooled analysis of studies including only a treatment arm, so no proper control groups are available. Studies present data about subjects before the treatment and after treatment, ...
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0answers
17 views

Calculation of I-squared in meta-analysis of diagnostic accuracy

I would like to calculate heterogeneity statistics (Cochran's Q, I-squared) for a meta-analysis of diagnostic accuracy. I successfully used the 'mada' package in R to calculate these statistics, but ...
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1answer
47 views

How to compare fixed effects of linear mixed models

I have two linear mixed models that I ran with the lmer function from the lme4 package. The models are identical except that I ...
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0answers
53 views

Simple Bayesian meta-analysis in R [closed]

Is there a simple way to conduct a Bayesian meta-analysis in R in order to support equivalence between the effects of two study types? E.g., Bayes factors would be perfect. So, for example I have ...
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0answers
26 views

Statistical test to compare two proportions

I am performing a meta-analysis comparing proportions of patients diagnosed with a disease based on 2 different diagnostic criteria. I have collected and pooled proportions rates (patients with a ...
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1answer
21 views

Meta Regression- Average AGe

I want to conduct a meta-regression, using the variable. The studies in my meta-analysis include studies, that compore two indipendent groups. My question: to calculate average age of a study - is it ...
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1answer
570 views

Calculating Cohen's d for pre-post/treatment-control design where treatment-control is also a repeated/within factor

I'm conducting a meta-analysis of studies that used pre-post/treatment-control designs. Most of them are mixed designs (pre-post is repeated/within; treatment-control is independent/between) with a ...
2
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1answer
36 views

What transformation can I use to enable a relatively unbiased meta-analysis of $\alpha$ reliability?

I want to meta-analyse reliability estimates. For simplicity, assume the reliability estimate in question is Cronbach's $\alpha$ (aka Guttman's $\lambda$-3). Various packages exist to do meta-analyses ...
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1answer
35 views

Meta-Analysis - Calculating SE from given ES

I have the following problem. I am trying to conduct a meta-analysis and I have an effect size estimation of some unpublished studies. Unfortunately, I don't have the Standard Errors for the mentioned ...
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1answer
268 views

Variance–covariance matrix in meta-analysis of variation metafor

I'm conducting a meta-analysis on estimating a gold standard measure from other simpler measures. To determine the error of estimation, I derived the standard deviations of the differences between the ...
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0answers
10 views

Pseudo replicas in meta-analysis [closed]

How do i control pseudo replicas in meta-analysis studies? I know I can randomize samples using Bootstrap for example, but how do I do this? Any clarification will be most welcome!
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1answer
73 views

Effect size calculation for Kruskal-Wallis mean rank test

I have a published paper in which I'm attempting to calculate the effect sizes for various outcomes. For a pre-post scale, the authors report the sample size, mean rank, and p-value for an outcome (...
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0answers
39 views

Correcting for reliability scores for Hedges g

I've received a revise and resubmit on my meta-analysis investigating the effects of a positive psychology intervention on depression and anxiety symptoms. I used Hedges' g as the effect size within a ...
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1answer
669 views

Performing subgroup analysis using the metafor package

When I performed a subgroup analysis on a catergorical moderator named "moda" (with two levels:m and n) in my data, ...
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0answers
15 views

Summary effect size of multiple dependent effect sizes

Problem Statement I am currently conducting a meta-analysis. At the moment, I am just calculating the effect size for each included study (for our purpose we chose the correlation coefficient r). ...
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2answers
2k views

Meta-analysis of proportions

I am conducting a meta-analysis on 20 studies. The outcome of interest in each study is represented by a proportion/percentage. The sample size n is known and is different for each study. I have ...
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0answers
22 views

Can multilevel meta analysis be random-effects model and/or fixed effects model?

I am learning multilevel meta-analysis (or, three-level meta-analysis e.g., https://bookdown.org/MathiasHarrer/...
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1answer
42 views

How to convert beta from logistic regression into cohen's d?

Is there a way to transform a coefficient from a logistic regression into a cohen's d value? I am trying to calculate the cohen's d for a study with a binary DV while controlling for another ...
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0answers
53 views

Meta-analyses using raw mean as Effect Size, instead of mean differences (e.g., Cohen's d)

I am writing up my meta-analysis using raw mean scores as effect sizes (i.e., reported mean scores on a certain standardized test) using the metafor package in R. ...
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0answers
33 views

How to convert sampling sampling variances for a meta-analysis using raw means as effect sizes?

I am conducting a meta-analysis using raw mean scores as effect sizes (i.e., reported test scores on a certain standardized test). I found a calculation formula for sampling variances provided by, e....
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2answers
220 views

Meta Analysis: Pooling samples or determine an average effect size

I am new to meta analysis and how I understood the terminology is that there are actually two ways of performing a meta analysis. Let's consider 5 clinical studies with fixed effects. Fixed effects in ...
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0answers
18 views

Trelllis plots in meta-analsysis [closed]

I am trying to plot, a trellis plot. But I get an error and I don't know what its means. ...
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1answer
83 views

What methods could be used to determine the validity of results from meta analysis besides conflict of interest?

Based on the answers I've read to a question1 on the Skeptics stack exchange, I began to wonder what methods besides the declaration of industry funding could be used to determine the validity of ...
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0answers
20 views

Multilevel regression meta-analysis : no existing package? (Edited)

The question is in the title. Meta-analysis with binomial distribution I'm trying to do a meta-analysis on occurence of an event across different studies. For each study $i$ ($i=1,\dots,N$), I have ...
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1answer
156 views

Backward model selection in metanalysis using 'glmulti' and/or 'metafor'

I want to test with a full model testing significant interactions with the main predictor 'Nadd' for my log transformed response ratio (...
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0answers
8 views

How do I use clinical trials as random effects in a cox regression model stratified according to trial for an individual patient data meta-analysis? [closed]

I am performing an individual patient data meta-analysis and pooling several trials. I have the data all combined in a single data set and want to fit it in a Cox regression model stratified according ...
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1answer
21 views

Prediction Intervals by meta package

I am using meta 4.9-5 package for conducting meta-analysis on correlation data. But I cannot figure out why it is unable to calculate lower and upper prediction intervals even I have set prediction = ...
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1answer
52 views

How to handle studies that don’t provide an estimate of effect size in a meta-analysis?

Say we want to survey the literature to find out the effect of Treatment A on Value B. Some studies provide an effect size estimate with confidence intervals and t-test results (e.g., “Treatment A ...
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2answers
232 views

Meta-Analysis on Effect Sizes with 95% Bayesian CI from CausalImpact R package

I am using the CausalImpact package in R to calculate the impact of a marketing intervention using Bayesian Structural Time Series. This methodology and package is explained in Broderson et al. 2015 ...
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2answers
137 views

Are there good alternatives to Cochran's Q test for heterogeneity in meta-analysis?

We used the Q test to determine heterogeneity with p-values <0.10. A highly recognised statistician commented that the Q test has low power and that it should not be used to determine presence of ...
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1answer
162 views

How do I translate logistic regression output into logged OR (and SE) for meta-analysis?

I'm attempting to conduct a meta-analysis using (logged) odds ratios, I'm using the Generic Inverse variance method (Review Manager) as some of my studies only report odds ratios and CIs (not raw data)...
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2answers
612 views

What does the p value mean in meta analysis results output?

What does the p value mean in a meta analysis results output? My meta analysis is looking at the proportion of people affected by PTSD. I am using the software OpenMeta Analyst which runs r in the ...
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2answers
1k views

Is precision-based (i.e. inverse-variance) weighting integral to meta-analysis?

Is precision-based weighting central to meta-analysis? Borenstein et al. (2009) write that for meta-analysis to be possible all that is necessary is that: Studies report a point estimate which can ...
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2answers
303 views

Meta-analysis and homogeneity — what did these guys do?

I appreciate any insight into this meta-analysis. This is a meta-analysis on alogliptin efficacy and safety. In the 2nd paragraph of the discussion that make this statement: Although heterogeneity ...
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1answer
108 views

Heterogeneity measures when pooling meta-analyses: what assumptions do we make?

I am looking at the possibilities and limitations of meta-meta-analysis (MMA), put differently, pooling the results of multiple meta-analysis. I realise that it is better to include primary studies, ...
1
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1answer
30 views

Regression multi-level meta-analysis with binomial data in R: no existing package? [closed]

The question is in the title. Meta-analysis with binomial distribution I'm trying to do a meta-analysis on occurence of an event across different studies. For each study $i$ ($i=1,\dots,N$), I have ...
11
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2answers
1k views

Can I include an effect size as an independent variable in a meta-regression?

My question is whether I can use an effect size $X$ as a dependent variable and another effect size $Y$ as the independent variable in a meta-regression? For example, I conducted a meta-analysis for ...
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3answers
50 views

Is it worth doing (single-armed) meta analysis if the studies' heterogeneity is very large?

I'm currently trying to perform a single-armed meta analysis of immunotherapy on breast cancer, which I believe this meta analysis will be the first among its intervention and cancer subtype. The ...
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1answer
362 views

How to calculate Inverse variance weight of several pearsons r correlations

I have a set of pearsons r effect sizes , converted to fishers z scores for meta analysis. I am wondering what data I need to calculate an inverse variance weight for each effect size and how I ...