Displaying 20 results from an estimated 300 matches similar to: "Metafor vs Meta vs Spreadsheet: wrong numbers"
2012 Aug 22
1
(Slight) calculation discrepancy in escalc (metafor package)
Hello,
I recently started using the metafor package (version 1.6-0) in R (2.15.1,
64-bit Windows 7) and noticed that I was getting slightly different values
when I manually calculated the standardized mean difference versus what
escalc was giving me. Here''s a very simple example:
escalc(measure="SMD", m1i=5,m2i=10,n1i=5,n2i=5,sd1i=1,sd2i=2,vtype="LS")
The result
2014 Nov 13
1
metafor - code for analysing geometric means
?Dear All
I have some data expressed in geometric means and 95% confidence intervals. Can I code them in metafor as:
rma(m1i=geometric mean 1, m2i=geometric mean 2, sd1i=geometric mean 1 CI /3.92, sd2i=geometric mean 2 CI/3.92.......etc, measure="MD")
All of the studies use geometric means.
Thanks!
Edward
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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
2013 Mar 02
1
Metafor "SMCR" Pre-Post Effect sizes
Dear all,
I am very grateful that Wolfgang Viechtbauer implemented the standardised mean change for dependent
groups. I was playing around a bit today, and I am not sure if I understand the "SMCR" procedure correctly. The documentation states that sd1i and sd2i are needed, but it seems to me that SMCR is ignoring sd2i (so Variances are not pooled). Instead, it uses sd1i (pre-test sd),
2012 Mar 25
2
avoiding for loops
I have data that looks like this:
> df1
group id
1 red A
2 red B
3 red C
4 blue D
5 blue E
6 blue F
I want a list of the groups containing vectors with the ids. I am
avoiding subset(), as it is
only recommended for interactive use. Here's what I have so far:
df1 <- data.frame(group=c("red", "red", "red", "blue",
2008 Mar 11
2
DO NOT REPLY [Bug 5318] New: Rsync assertion in check_prior() when using --append
https://bugzilla.samba.org/show_bug.cgi?id=5318
Summary: Rsync assertion in check_prior() when using --append
Product: rsync
Version: 3.0.0
Platform: Other
OS/Version: FreeBSD
Status: NEW
Severity: normal
Priority: P3
Component: core
AssignedTo: wayned@samba.org
ReportedBy:
2008 Oct 13
1
Unkown namespace / sieve
Hello,
I use dovecot + dspam and a very simple global sieve script :
require "fileinto";
if header :contains "X-DSPAM-Result" "Spam" {
fileinto "SPAM";
stop;
}
with dovecot 1.0 all run fine, but moving to 1.1 I experience this in
maillog :
Oct 13 10:31:52 h8h1 deliver(ml at sd2i.com): msgid=<8a24c15885037554724ff966f5458592 at
2012 Mar 28
0
Major update: meta version 2.0-0
Version 2.0-0 of meta (an R package for meta-analysis) is now available
on CRAN. Changes are described below.
Yours,
Guido
Major revision
R package meta linked to R package metafor by Wolfgang Viechtbauer to
provide additional statistical methods, e.g. meta-regression and other
estimates for tau-squared (REML, ...)
New functions:
- metareg (meta-regression)
- metabias
2012 Mar 28
0
Major update: meta version 2.0-0
Version 2.0-0 of meta (an R package for meta-analysis) is now available
on CRAN. Changes are described below.
Yours,
Guido
Major revision
R package meta linked to R package metafor by Wolfgang Viechtbauer to
provide additional statistical methods, e.g. meta-regression and other
estimates for tau-squared (REML, ...)
New functions:
- metareg (meta-regression)
- metabias
2008 Apr 23
4
disconnect error
a user complain about suddent disconnect error from time to time (he's
using pop3 with Apple Mail)
Looking at dovecot logs I discover that, each time the error shows up
for him, I have this :
dovecot: pop3[95137]: Info: user=<dan at userdomain.com> Disconnected
top=0/0, retr=0/0, del=0/4, size=127101
but all other "regular" pop3 session looks like this one :
dovecot:
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
2009 Jul 24
1
metafor
I had found the author's (Wolfgang Viechtbauer) earlier meta-analytic code in R, MiMa, useful. so I have been exploring metafor using an example dataset from MiMa. metafor provides a lot more. However, MiMa provided parameter estimates, standard errors, z values, etc. for individual moderators in the meta-analysis, but I don't see how to obtain these from metafor. Have you any help
2013 Mar 15
1
metafor - multivariate analysis
Dear Metafor users, I'm conducting a metaanalysis of prevalence of a particular behaviour based on someone elses' code. I've been labouring under the impression that this:
summary(rma.1<-rma(yi,vi,mods=cbind(approxmeanage,interviewmethodcode),data=mal,method="DL",knha=F,weighted=F,intercept=T))
is doing the multivariate analysis that i want, but have read that
2011 Aug 17
3
questions about "metafor" package
Hello,
I would like to do a meta-analysis with the package « metafor ». Ideally I would like to use a mixed model because I’m interested to see the effect of some moderators. But the data set I managed to collect from literature presents two limits.
- Firstly, for each observation, I have means for a treatment and for a control, but I don’t always have corresponding standard
2011 Oct 03
1
Meta-analysis of test statistics in "metafor" package?
Hi -
I am conducting a meta-analysis and I have a matrix of f-statistics, Ns and
dfs from a series of studies that tested for an interaction in a 2x2 anova.
I'd like to test whether the 2x2 interaction is significant in the
aggregate.
Similarly, I have a matrix of chi-square statistics that I'd like to
meta-analyze.
How can I input these test statistics into the "metafor"
2012 Jan 11
1
meta-analysis normal quantile plot metafor
Hello,
I once used the metawin software to perform a meta-analysis (see
metawinsoft, Rosenberg et al.) and produced normal qqplot to test for
a potential bias in the dataset.
I now want to re-use the same dataset with the package metafor by W.
Viechtbauer (great package btw).
I run the qqnorm.rma.uni function. I use standardized effect sizes as
in metawin.
QQplot generated with metafor differs
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
2012 Aug 01
1
"metafor" package, proportions: single groups wrt to a categorical dependent variable
Dear Dushanthi,
Please keep your e-mails on the R-Help list, where Michael has already given you some excellent advice. As Michael already explained, metafor can handle proportions, but does not have any specific functionality for categorical variables with more than 2 levels (at the moment). So, if it is logical and possible to do so, you could collapse the levels of the categorical outcome to 2
2009 Jun 05
1
New Meta-Analysis Package (metafor)
A new package is now available via CRAN, called metafor.
The metafor package consists of a collection of functions for conducting meta-analyses in R. Fixed- and random-effects models (with and without moderators) can be fitted via the general linear (mixed-effects) model. For 2x2 table data, the Mantel-Haenszel and Peto's method are also implemented. The package also provides various plot
2012 Apr 04
1
using metafor for meta-analysis of before-after studies
Greetings,
I wish to conduct a meta-analysis for which the outcome is a continuous
variable measured on the same individuals before and after an intervention.
Hence, the comparison is not made between two groups, but within groups, at
diffrent times.
Each study reports the mean outcome and SD before the intervention and the
mean outcome and SD after the intervention. While p-values for