Meta-analysis refers to methods focused on contrasting and combining results from different studies, in the hope of identifying patterns among study results, sources of disagreement among those results, or other interesting relationships that may come to light in the context of multiple studies.

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Meta Analysis for one proportion

I have data summarizing proportion of events from 5 different papers. The proportions are in %'s. For example, in paper number 1, there was a report of 2000 people and a proportion of 10%. I want a ...
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1answer
23 views

Q-Test of Heterogeneity for only two effect sizes?

I am using the Q-Test of Heterogeneity to investigate if several effect sizes derived from two different studies are significantly different from each other. More precisely, I have, for every effect ...
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16 views

Calculating a pooled estimate

I am writing a systematic review on certain imaging studies and I was hoping to add a meta-analysis of the sensitivities of the various modalities reported on. My goal was to put together a forest ...
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1answer
45 views

Why does Stouffer's method work?

It seems like a fairly straightforward question, but when I really think about it, Stouffer's method doesn't make sense to me. This is why: Assume a two-tailed hypothesis. You first calculate $z_i$ ...
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48 views

Estimating the difference between adjusted and unadjusted meta-analytic effect sizes

I am working on a meta-analysis of standardized mean differences for which researchers report a variety of unadjusted data and data that are adjusted for one or two covariates. In this research ...
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21 views

Combining effect sizes in binary data

I'm working on combining effect sizes for a meta-analysis when one study reports multiple effects for the same construct. To accomplish this, I'm using the equation provided in the Borenstein ...
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24 views

Logit or arcsine transformation for proportion in meta-analysis

I am performing a meta-analysis with 137 study arms. From each arm I have extracted a proportion of a disease. Here are my proportions: ...
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15 views

What is the limitation with using a pooled standard deviation in a dependant sample?

I am not very experienced in statistics, but want to perform a meta-analysis on a number of pre-post studies. The studies have relatively small sample size ranging from around 10-38 subjects. They are ...
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20 views

Meta Analysis for Binary Outcome, Two Groups, Pre and Post

This seems like a straight-forward problem, but I can't seem to wrap my head around it. I have a binary outcome (Presence/Absence of a condition for a patient), and an intervention (educational ...
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15 views

Forest Plot shows negative estimate(slope) but mean trends are increasing.

I'm conducting a meta-analysis which shows obvious increasing trends amongst means. However when I plot my forest plot, all values are below 0. As far as I'm aware, when values are below 0, it shows a ...
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26 views

User-defined weights in meta-analysis accounting for the length of the study

I am conducting a meta-analysis in the field of ecology in which the effect size is the log ratio of the means (control and treatment). When fitting the model with ...
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24 views

Estimate ROC curve using binormal distribuiton

I am conducting a meta-analysis on diagnostic studies but for each study I have only mean and standard deviation reported. How can I estimate the ROC curve using the binormal assumption in R ? Tks,
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29 views

Methods for meta-analysis: z-transform (Stouffer's approach) vs. Fisher's method vs… infinite others? [duplicate]

Fisher's method and Stouffer's approach (z-transform) for meta-analysis roughly follow the same scheme: take the p-values from some different experiments on the same hypotheses apply to them some ...
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2answers
48 views

Heterogeneity statistics with fixed effects model in RevMan

Since a fixed-effects meta-analysis assumes that the studies are all estimating the same underlying effect, when the Cochrane RevMan software reports a Q and $I^2$ statistic with a fixed-effects ...
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48 views

Calculate combined variance from multiple dependent time-points for meta-analysis with {metafor} [closed]

I have a dataset, which is a subset containing only the studies that contain multiple measurements over time within a study, and hence not independent. Example: ...
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27 views

Comparing raw non-normal data with a mean and SD of non-normal data

I have raw data, which are non-normally distributed (negative binomial, or if converted to densities, compound Gamma-Poisson), as well as a mean and standard deviation (SD) of another data set ...
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8 views

How can we construct cumulative meta analysis plot after doing proportion meta analysis

Need to do cumulative plot for proportion meta analysis. Suggest software
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16 views

Meta regression in proportion meta analysis

I completed proportion meta analysis using stuart-ord method. Now need to do meta regression. I used stats direct for proportion meta analysis. Previously I did meta regression using comprehensive ...
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1answer
62 views

Properly calculate mean and SE for meta-analysis

I want to perform a meta-analysis, for which I have data from 30 different experiments, each of them with two different treatments. I have three different types experiments based on how the data are ...
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1answer
22 views

Interpreting stripe like shapes on funnel plot from meta-analysis

I have a set of 130 measurements from about 30 different studies. I have made a random effects meta-analysis of SMD and ROM. I used the DL method. I also made funnel plots to check for publication ...
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1answer
38 views

Fitting nonlinear meta regression models to data

I have a collection of data, obtained from different studies. To plot the ratio of means against different CO2 concentrations, I used a random effects model with a continues predictor (the CO2 ...
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31 views

Bayesian random effects meta-analysis on the risk ratio with r2jags

Following the work of Warn 2002 I am trying to set up the model for a Bayesian meta-analysis on the risk ratio and the odds ratio. I am using R together with R2jags to fit a simple RE MA model. ...
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38 views

Failed to reduce deviance while using “lme4 : glmer ”

this is my first post, so I will try to make it as clear as possible. Hopefully is not something trivial and I am just stuck. I am performing meta-analysis using the glmer function of the lme4 ...
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23 views

How to compare latent mean difference from Measurement Invariance with cohen's d from a meta-analysis?

I was wondering if it is possible to compare latent mean differences estimated in a scalar invariance model to an overall Cohen's d found in a meta-analysis. Is there a way to convert one value to the ...
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24 views

How should I combine this binary scale with this 4-point scale?

I'm doing a meta-analysis and I want to combine the results of two questionnaires. One questionnaire has 30 questions about whether you've experienced certain traumatic life events. They're all ...
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1answer
24 views

Fitting curves to means and variances from multiple samples

I have data on a variable measured in multiple longitudinal samples. I do not have the individual-level data for each sample, just the sample means and variances at each time point. The samples do not ...
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12 views

If doing a meta-analysis with R, using log hazard ratios, do I supply the variance/SE or the log variance/SE? [duplicate]

As above, really! I have a load of trials for which I have the HR, the standard error of the HR, and n. I can either supply the variance with vi=(SE*sqrt(n))^2 or ...
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1answer
56 views

Meta-analysis of trials given hazard ratios

I'm trying to do a meta-analysis in R (using metafor) of trials where the outcomes are hazard ratios and I'm given the 95% CI for them and/or the standard error and n. So if I have columns like: ...
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1answer
40 views

Can I get an Odds Ratio (or other effect size) from two proportions and a p-value?

I am conducting a meta analysis that is comparing dichotomous outcomes for two groups. So for each study, I have the proportion of the outcome for both groups and the sample size of each group, and I ...
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1answer
57 views

Metafor rma.mv function: missing estimates for two levels of a categorical moderator

I am conducting a meta-analysis with several categorical moderators and one continuous moderator; I am also interested in an interaction between two of the moderators (outcome and scale). I have ...
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1answer
58 views

How to convert the standard error of the log odds ratio to the odds ratio standard error

I am using the log odds ratio (and its standard error) for meta-analysis. I want to convert back to odds ratio to write up the results... maybe i'm putting in the wrong search terms but can't find ...
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14 views

User weight specification in Meta-analysis using STATA

I want to perform Meta-analysis in STATA using User define weight option "wgt()", i.e., metan coef, fixed wgt(weight-variable). However, the model is not running, stata says, " too few variables ...
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11 views

How to manually do Bayesian fixed effects meta-analysis?

Assume $Y_i \sim Normal(\mu, \sigma_i)$ for $i = 1, 2, 3, \ldots, k$ independent studies. Here I assume $\sigma_i$ is known. The prior distribution is $\mu \sim Normal(\mu_0, \sigma_0)$. What will be ...
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1answer
68 views

Method of meta-analysis of studies to determine mean blood level

Generally meta-analysis is done to determine the efficacy of some treatment as compared to controls. Is it possible to do a meta-analysis of different studies for mean blood level of a chemical, its ...
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23 views

Explanation of heterogeneity

Following is the output of meta-analysis of five fictitious studies: ...
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1answer
52 views

How to choose between fixed effects and random effect meta-analysis

In meta-analysis packages, both fixed effects and random effects models are available. How do one choose between these 2 models? Since one is assessing different studies, should one not choose random ...
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25 views

How to compare the continuous outcome of two group of studies in a meta synthesis?

While doing a meta synthesis, I would like to state if there is a difference in the compost quality (e.g. the carbon content) between studies carried out in tropical and temperate region. Within each ...
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1answer
58 views

How to combine data several studies with events?

I have a compilation of following data on 10 studies, all of which had 2 groups: a control group which received usual treatment and an active group which received an intervention. The subjects were ...
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19 views

ANOVA effect size for meta-analysis

I am currently planning to perform a meta-analysis. I have 3 studies with different sample sizes n=22,n=149,n=155 I am measuring the effect of treatment in each group using an ANOVA in R (more than ...
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1answer
41 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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1answer
52 views

Metafor package: bias and sensitivity diagnostics

I am conducting a multi-level meta-analysis that includes some articles with multiple outcomes. Therefore I am using the rma.mv() function. Example code: ...
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45 views

Alternate weighting schemes for random effects meta-analysis: missing standard deviations

I am working on a random effects meta-analysis covering a number of studies which do not report standard deviations; all studies do report sample size. I do not believe it is possible to approximate ...
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38 views

Calculating the covariance of effect sizes for multiple-treatment multiple-enpoint studies

I'm interested in finding the covariance of effect sizes for multiple-treatment multiple-outcome design given the scenario below. Gleser and Olkin (2009) provided the formula for the estimating the ...
3
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1answer
104 views

Simulating non-normal correlated data for Bayesian regression

I'm interested in generating data for three separate datasets where each contains three IVs and a single DV that are correlated with one another based on meta-analytic data. For example, I would like ...
3
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1answer
56 views

What are the effects of continuity correction in binomial meta-analysis in the metafor package?

The metafor package in R can be used to fit the random effects model with the exact binomial likelihood as described in Stijnen et al. (2010). The ...
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1answer
47 views

Most appropriate way to construct overlapping dummies

What would be the most appropriate way to construct dummies with theoretical overlap? I'm doing a meta-regression of studies looking at the effect of certain interventions on X. Some studies use ...
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30 views

How do I calculate the variance of a mean difference effect size that has been converted to Fisher's z for meta-analysis?

To be able to compare different types of effect sizes, I am converting my effect sizes that are originally mean differences into correlation coefficients. I am using the following formula: d <- (t ...
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43 views

Meta-analysis in R using SE and weights based on number of years of the experiments

I have a dataset with this format, containing different experiments and mean and SE values for two treatments (amb and elev), to ...
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8 views

Variable selection algorithm based on meta study

Suppose I would like to conduct a survey and want to know which variables to include. Literature review and theoretical guidance both help. What I would like to know is whether there is a way to do a ...
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33 views

Meta-analysis statistics required

I need to know the appropriate statistic to use in a meta-analysis. I want to compare the effect size for three hypotheses - that there are significant groups differences firstly between treatment ...