Displaying 20 results from an estimated 2000 matches similar to: "Extract confidence intervals from rma object (metafor package)"
2012 Jul 24
1
Annotate forest plot 'forest.rma()' for meta-analysis with metafor package
Dear R-experts,
The forest.rma() function from the metafor package creates nice forest
plots for presenting the results of a meta-analysis. These plots can be
annotated for e.g. giving names to the columns. E.g. as in the
documentation of the package:
data(dat.bcg)
### meta-analysis of the log relative risks using a random-effects model
res <- rma(ai=tpos, bi=tneg, ci=cpos, di=cneg,
2011 Aug 05
1
Main-effect of categorical variables in meta-analysis (metafor)
Dear R-experts!
In a meta-analysis (metafor) I would like to assess the effect of two
categorical covariates (A & B) whereas they both have 4 levels.
Is my understanding correct that this would require to dummy-code (0,1) each
level of each covariate (A & B)?
However I am interested in the main-effects and the interaction of these two
covariates and the dummy-coding would only allow to
2010 Mar 02
1
add a header to a forest plot (metafor)
Dear R-community,
I'm currently trying to assemble a forest plot using the "forest" function
from package "metaphor".
Works well. Even the regular "main"-argument works for adding a title to the
graph.
However, I would like to add one top row which explains the nature of the
columns. Very much like the usual header in spreadsheet programs.
For example:
2011 Dec 10
3
Overlaying density plot on forest plot
Dear R User,
Please, I am new to R. I want to overlay density plot for predictive interval pooled result in meta-analysis. http://addictedtor.free.fr/graphiques/graphcode.php?graph=114
Regards
Frank Peter
2011 Jan 12
1
metafor/ meta-regression
Hi I have tryed to do the meta-regression in metafor package, but I
would like to get the standardized coefficients for each variable, however in
command:
Ø res<-rma.uni (yi, vi,
method="REML", mods=~cota+DL+uso+gadiente+idade, data= turbidez)
I just have the coefficients no standardized (estimate) of the multiple
regression.
What I need to do?
Thanks
Fernanda Melo
2012 Aug 02
2
metafor- interpretation of moderators test for raw proportions
Hello metafor users,
I'm using metafor to perform a single-effect summary estimate of the raw
proportion of patients experiencing a post-operative complication, and I'm
interested in seeing if this proportion differs between the three most
commonly used surgical techniques. The software is working as expected, but
I would like to double check on the interpretation of my mixed-effect model
2011 Apr 11
1
forest + igraph ?
Hello,
Is it possible to have two meta-plots in one graph (not par(mfrow=c(2,1))? But somthing like
library(metafor)
library("igraph")
if (interactive()) {
forest(dat.Treat$RR, ci.lb=dat.Treat$lower, ci.ub=dat.Treat$upper, xlab="Relative Risk",slab=dat.Treat$ID,refline=1)
forest(dat.Control$RR, ci.lb=dat.Control$lower, ci.ub=dat.Control$upper, xlab="Relative
2013 Mar 14
3
Create patterns within a plot?
Dear All,
As an attempt to highlight the overall pattern in a Forest plot, I would like to "highlight" the area around HR=1. I cannot find any simple tools for painting a grey ribbon between 0.9 and 1.1. Any suggestions?
Thank you in advance!
Cheers, Patrik
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2013 Jan 05
3
package metafor: error when setting 'col' and 'at' for a forest plot
I am using metafor to create forest plots. This code gives me the expected
plot (setting x axis tick marks):
forest(forest$OR, ci.lb=forest$Low, ci.ub=forest$High, at=log(c(.05, .25,
1, 10)), slab=forest$SNP, atransf=exp)
As does this (setting colors):
forest(forest$OR, ci.lb=forest$Low, ci.ub=forest$High, col=c(1,2,3),
slab=forest$SNP, atransf=exp)
But if I try to set both 'at' and
2011 Jul 27
1
Converting F-value from ANOVA to cohen's d in meta-analysis (metafor-package)
Dear R-experts!
Running a meta-analysis (using the magnificent metafor-package), I use
cohen's d as a main outcome measure in a random-effects model.
For most of the samples cohen's d is derived form a comparison of two groups
(A & B). However some studies report results from an ANOVA (one-factor with
three levels: C,D,E) whereas two groups (C,D) correspond to one group in the
other
2009 Dec 04
1
z to r transformation within print.rma.uni and forest from the package metafor
Dear R community,
I'm using the ,metafor'-package by Wolfgang Viechtbauer (Version: 0.5-5) to
calculate random-effects meta-analyses using Correlations and Sample Sizes
as the raw data.
(By the way: Really a nice piece of work, Wolfgang! Thanks heaps.)
I specified the "rma.uni' function so that it looks like this:
MAergebnis<-rma.uni(ri=PosOutc, ni=N,
2011 Sep 08
1
predict.rma (metafor package)
Hi
(R 2.13.1, OSX 10.6.8)
I am trying to use predict.rma with continuous and categorical variables. The argument newmods in predict.rma seems to handle coviariates, but appears to falter on factors. While I realise that the coefficients for factors provide the answers, the goal is to eventually use predict.rma with ANCOVA type model with an interaction.
Here is a self contained example
2010 Jul 02
1
metafor and meta-analysis at arm-level
Hi,
I have been looking for an R package which allowed to do meta-analysis
(both pairwise and network/mixed-treatment) at arm-level rather than at
trial-level, the latter being the common way in which meta-analysis is
done.
By arm-level meta-analysis I mean one that accounts for data provided at
the level of the individual arms of each trial and that does not simply
derive the difference between
2011 Jan 12
1
Metafor vs Meta vs Spreadsheet: wrong numbers
Hello,
I experimented the Metafor and Meta packages in the scope of replacing Excel
for meta-analysis. I performed the first working example provided in Michael
Borenstein's book "Introduction to Meta-Analysis" with Excel, Metafor and Meta.
The numbers given by my spreadsheet, which I validated from Borenstein's book,
conrespond quite closely to those given by Meta, but
2012 May 05
3
metafor
Dear users of metafor,
I am working on a meta-analysis using the metafor package. I have a
excel csv database that I am working with. I am interested in pooling
the effect measures for a particular subgroup (European women) in this
csv database. I am conducting both sub-group and meta-regression.
In subgroup-analyses, I have stratified the database to create a
separate csv file just for European
2012 Jan 14
1
metafor: weights computation in Mantel-Haenszel method
Dear R users,
In metafor 1.6-0, the Mantel-Haenszel method is implemented by the rma.mh() function. I have observed that the sum of the weights computed by weights(x) doesn't add to 100% when x is an object of class rma.mh. The consequences of this fact can be clearly seen when a forest diagram is drawn with forest(x), which calls weights(x) (or more precisely, the method weights.rma.mh()
2012 Sep 07
2
metafor package: study level variation
Hello. A quick question about incorporating variation due to study in the metafor package. I'm working with a particular data set for meta-analysis where some studies have multiple measurements. Others do not. So, let's say the effect I'm looking at is response to two different kinds of drug treatment - let's call their effect sizes T1 and T2. Some studies have multiple
2010 Jan 04
1
metafor: using mixed models
Dear all,
I'm currently applying a mixed model approach to meta analysis using the
package metafor. I use the "model.matrix()" function to create dummy
variables. The option btt gives me the combined test for the dummies.
Problem is, I don't know which indices I have to use, and can't really
figure it out from the help file and the examples. I use following code :
X <-
2013 Jan 23
1
mixed effects meta-regression: nlme vs. metafor
Hi,
I would like to do a meta-analysis, i.e., a mixed-effects regression,
but I don't seem to get what I want using both the nlme or metafor packages.
My question: is there indeed no way to do it?
And if so, is there another package I could use?
Here are the details:
In my meta-analysis I'm comparing different studies that report a
measure at time zero and after a certain followup
2009 Aug 13
1
metafor random effects meta-analysis
Hello,
Great to see the new metafor package for meta-analysis.
I would like to perform a meta-analysis in which I initially calculate the intercept of the model with a nested random-effects structure. In lme, this would be
model<- lme(v3~1, random=~1|species/study, weights = varFixed(~Wt), method = "REML")
where multiple effects sizes are measured for some studies and more than