The meta-analysis tag has no wiki summary.
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What is the difference between a frequentist approach with meta-analysis and a Bayesian approach?
Say I am performing an analysis looking at a particular health measure. I am interested in the difference in that measure between patients and controls and wether or not the difference is different ...
5
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2answers
108 views
Can I incude 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 a the independent variable in a meta-regression.
For example, I conducted a meta-analysis for the ...
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1answer
28 views
How can I perform a meta-analysis on variables which are not normally distributed?
I am working on a project to estimate a radiation protection value called DDREF which is the ratio of two regression coefficients. Specifically:
$DDREF$ $=$ $a/B$
where
$E$ ~ $a*D+B*D^2$
$D$ is ...
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0answers
25 views
Making a contour-enhanced funnel plot for a RE meta-analysis [migrated]
I am trying to make a contour-enhanced funnel plot for a random-effects meta-analysis model. I am using the funnel.rma() function from the ...
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0answers
38 views
How many chains should we choose in multi-treatment meta-analysis using MCMC and WinBugs
I am learning to undertake multiple treatment comparison meta-analysis (aka network meta-analysis or MTM) using WinBugs. One of the specifications are choosing the number of chains to run in the MCMC ...
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1answer
29 views
How to model repeated measures' results in meta-analysis?
I am developing network meta-analysis BUGS model that I will use to compare Hazard Ratios in studies that assume Box Proportional Hazard model.
As input I am given pairs: (log HR, its standard ...
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2answers
25 views
Combining treatment as usual and experimental placebo control groups in one meta analysis
I'm conducting a sr and meta analysis of interventions that target children with ADHD in school settings. The studies reviewed include both treatment as usual comparisons and experiments placebo ...
2
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1answer
122 views
Principled ways of constraining $E[Y]=0$ when one of your regressors $\rightarrow$ 0
Consider the following ridiculous example. There is a real, non-ridiculous research question here, I promise -- I'm just a little bit uncomfortable posting what I'm working on on the internet in ...
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29 views
How to - meta-analysis and forest plots using Beta correlation coefficients
Does anyone knows how to meta-analyse and create forest plots using beta-correlation coefficients?
4
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1answer
57 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 ...
0
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1answer
96 views
Using mvmeta to perform a network meta-analysis
A few months ago, I posted these two questions about practical considerations in collecting data for a network meta-analysis and the available R packages that can analyze such data. For those ...
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38 views
Publication bias in meta-analysis of single case studies
Is there a way of investigating publications bias in a meta-analysis of single case studies?
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0answers
37 views
How to use a meta-analysis to assess the equivalence of two different procedures?
I'm making a comparison of two surgical procedures, and I want to know how I can analyze the data I have for a meta-analysis. The overall surgical procedure is the same, but some authors choose to ...
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2answers
55 views
Is it standard practice to omit studies lacking an estimate of sample standard deviation from meta-analysis?
It appears common among meta-analyses to omit studies that do not provide an estimate of sample standard deviation. For example, a previous question reviews some ways to estimate $\sigma$ from ...
0
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1answer
80 views
How to create a forest plot using the effect estimates (OR/RR and the confidence intervals) if no raw data is available?
I want to combine studies in a meta-analysis however I dont have raw data available to calculate original OR (95% CIs) from start. So I wonder if there is any way to create a forrest plot using this ...
3
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2answers
213 views
What is the equation for combining standardized mean differences across multiple studies?
I am trying to come up with a combined/pooled standardized mean difference for meta-analysis of a dozen or so studies that have the same binary predictive groups and the same continuous outcome ...
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2answers
382 views
Multiple imputation for outcome variables
I've got a dataset on agricultural trials. My response variable is a response ratio: log(treatment/control). I'm interested in what mediates the difference, so I'm running RE meta-regressions ...
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1answer
180 views
Deriving effect sizes form pre-post treatment design in R?
This question is related to my previous post.
In case of a meta-analysis of a pre-post treatment design I have data given from 5 studies that tested subjects pre- and post-treatment on a continuous ...
2
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1answer
108 views
Meta-analysis in R of pre-post treatment design studies
I would like to conduct a meta-analysis in R of studies using a pre-post treatment design. In every individual study 4 different subgroups of patients have undergone a pharmacological treatment and ...
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3answers
428 views
Pros and cons of meta-analyses
I have been considering doing some meta-analysis for a particular field of study in evolution, but before I go any further I would like to know; what are the positives and negatives of the process? ...
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3answers
122 views
Bayesian meta analysis of residual standard deviation using BUGS
I have a small number of studies where the same model was calculated and want to infer the typical standard residual deviation. I have the degrees of freedom, the sum of the squares SSR and the mean ...
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3answers
562 views
What causes the discontinuity in the distribution of published p-values at p < .05?
In a recent paper , Masicampo and Lalande (M-L) collected a large number of p-values published in many different studies. They observed a curious jump in the histogram of the p-values right at the ...
3
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1answer
76 views
Correcting biased polling
Let's say I'm polling for a binary election in different states with known biases. Furthermore, let's say I only manage to poll only a small sample of people in each of these states. How would you ...
5
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1answer
328 views
How to calculate weighted Hedges' g effect size in meta-analysis when some effect sizes share a control group?
I am trying to do a meta-analysis using Hedges' G as the effect size.
Questions
Some of the studies have different groups but the same control group. How does this change the computation and ...
3
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1answer
89 views
Individual patient data meta-analysis with SD's as outcome measure
I'm reading the results of an individual patient data (IPD) meta-analysis. The outcomes of the study is expressed in standard deviations (SD's). Comparisons between groups are stated as 0,23 (95% CI ...
4
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1answer
136 views
Practical data collection tips for performing a network meta analysis (mixed treatment comparisons)
As described previously in this post, I am currently working through issues with conducting a network meta analysis (also known as mixed treatment comparisons). For those unfamiliar with this method, ...
4
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1answer
252 views
R software implementation of combining mixed treatment comparisons and meta-regression
I am currently conducting a meta-analysis in which I need to use a mixed treatment comparison method. As I understand it, this method works in the following way:
Say you have a group of studies that ...
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0answers
136 views
Orwin's Fail safe N calculation - critical d value
I'm trying to calculate Orwin's fail safe n but cannot figure out all of the terms in his equation - specifically, how is the critical value of d calculated?
Thank you
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0answers
1k views
How do you make forest plot with difference in means and CI?
I have to prepare forest plot for anti-hypertensive drugs. So far, I have seen forest plots that used odds ratios. I have difference in mean change in blood pressure in 2 groups along with 95% ...
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0answers
63 views
Which effect size measure is appropriate for meta-analysis of pharamcogenetic studies
I have been poked for using cohen's d as an effect size statistic in a meta-analysis of pharmacogenetic studies. Apparently is has been argued that (McGough et al., 2009) cohen's d is not appropriate ...
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0answers
272 views
Comparing logistic coefficients on different logit models?
I've developed a logit model to be applied to six different sets of cross-sectional data. All the models have same independent variables but the sample size is different for each model. What I'm ...
2
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2answers
71 views
How to account for aggregation over subjects in meta-analysis?
I conduct a small meta-analysis of the preferences ratings for objects in two different conditions. I compute Fisher's z and SE for each study.
1) There are studies with totally different number of ...
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2answers
144 views
Is it 'legal' to publish a meta-analysis online?
I would like to present a meta-analysis on a homepage. This should include a forest plot to visualize the effect sizes from individual studies as well as the summary statistics. I was wondering ...
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0answers
124 views
PLINK meta-analysis method
I am trying to determine exactly what method PLINK uses for meta-analysis. I can't find it in the program documentation/FAQ anywhere. Inverse variance? (given the meta command only requires effect ...
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38 views
Inconsistent estimates of H in a meta-analysis
I'm working on a meta-analysis and have computed H based on a maximum likelihood estimate of tau^2. This value of H was 0.99. However, as an independent check, I also computed H as the standard ...
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1answer
509 views
Calculating a pooled odds ratio from an adjusted odds ratio?
I have individual adjusted odds ratios from different articles, and I want to combine them to calculate a pooled odds ratio, e.g., aOR 2.13(1.43-3.18) and ...
4
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1answer
143 views
Whether to apply structural equation modelling separately to each of a set of heterogeneous correlation matrices in a meta-analysis context?
I'm in the process of performing an Structural Equation Modelling (SEM) meta-analysis on some psychological data. Ultimately I want to examine a mediational model based on a set of correlation ...
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2answers
814 views
What is the difference between fixed effects model and random effects model for a meta-analysis of sample correlations?
What is the difference between fixed effects model and random effects model for a meta-analysis of sample correlations ?
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2answers
313 views
How to correct for inter-experimental variation in cell culture research?
I am testing cell cultures. I grow cells in a "control media" for 2 weeks. During these 2 weeks, the cells produce an antibody, and at the end of the 2 weeks, I measure the levels of the antibody. ...
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2answers
206 views
Why not perform meta-analysis on partially simulated data?
Background:
A typical meta-analysis in psychology might seek to model the correlation between two variables X and Y. The analysis would typically involve obtaining a set of relevant correlations ...
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100 views
Meta-analysis using GWAS datasets of different diseases
It is well known that in Meta-analysis of Genome-wide association studies (GWAS) we combine the results of independent studies to get a pooled effect estimates (Odd ratios or betas) in order to ...
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2answers
294 views
How to conduct a meta-analysis using raw data?
I think meta-analyses are a great way of exploring a hypothesis when available evidence is heterogeneous. Usually however when conducting a meta-analysis one puts aggregated data in a model, possibly ...
4
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3answers
252 views
Two studies, opposite results: Am I allowed to compute an overall mean using random-effect model?
I am performing a meta-analysis. I have a subgroup made only of 2 studies and they show opposite results. The 1st has excellent outcomes the 2nd very bad ones.
Is it true that I am not allowed to ...
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2answers
170 views
Calculating standard error for funnel plots
I'm a programmer, with a decent but not-expert knowledge of stats, and I'm working through these instructions for how to create funnel plots.
I know that there are better ready-made tools (e.g. R) ...
3
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1answer
597 views
Odds ratio and confidence interval in meta-analysis
I need to calculate the pooled odds ratio and associated 95% confidence interval for meta-analysis of 2 studies about the risk of bleeding. The only information I have is the odds ratios and 95% ...
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2answers
872 views
Does transformation of r into Fisher z benefit a meta-analysis?
Usually r is transformed into Fisher z to test difference between two r values. But, when a meta-anlysis is to be performed, why we should take such a step ? Does it correct for measurement error or ...
2
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1answer
318 views
When to use correlation as effect size when performing meta-analysis with diverse predictors?
I am a PhD student and am conducting a literature review on musculoskeletal physiotherapy and am struggling to get guidance on this subject as most health researchers conduct meta-analyses of ...
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1answer
237 views
Combined odds ratio
I wonder if there's a way to calculate the combined odds ratio for certain SNPs in a meta-analysis of a several GWAS, even when you don't have the SE, neither beta, for each individual study?
Thank ...
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2answers
232 views
Meta-analysis in R with multiple SNPs
I'm conducting a meta-analysis on two genome wide association studies (GWAS), each consisting of 150 SNPs, for which I computed summary statistics for association.
I'm using the R package meta and the ...
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1answer
287 views
How to combine many Goodman-Kruskal gamma measures?
I have 5 samples (from the same population). I want to calculate the Goodman-Kruskal gamma ($\gamma$) for the population, based on the gamma of the 5 samples ($G_i$).
Each data has 2 ordinal ...
