[R] meta-analysis normal quantile plot metafor

[Michael Dewey]

At 12:15 16/01/2012, Ricc wrote:
>Hello,
>I used the default parameters:
>- envelope: default is TRUE
>- level: the default is to take the value from the object (I do not
>understand this very well)

When you specified your original model to rma.uni you either 
specified the level or let it default (to 95). That value is stored 
in the object returned by rma.uni and used by qqnorm.rma.uni unless 
you override it. You can see what is in the object returned by 
rma.uni by using str.

>- bonferroni : no
>- reps : default is 1000
>- smooth: default is TRUE
>- bass : default is 0
>
>  I used no other arguments.
>
>
>2012/1/13 Michael Dewey <info at aghmed.fsnet.co.uk>:
> > At 15:53 11/01/2012, Ricc wrote:
> >>
> >> 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.
> >
> >
> > I think it would help if you said which parameters you used to control the
> > envelope. Did you smooth it? Did you use the Bonferroni correction?
> >
> >
> >
> >> QQplot generated with metafor differs from the plot obtained with
> >> metawin: most of the datapoint fall outside the confidence envelope
> >> (using the same confidence level). I don't understand very well how
> >> the "pseudo confidence envelope" was created in metafor. Is it more
> >> conservative than that from metawin or created using the package
> >> envelope ? Unfortunately I do not have access to metawin's code so
> >> that I cannot compare implementations but the manual let me think that
> >> metawin print classical confidence interval...
> >>
> >> Thanks for input !
> >> Ricc
> >>
> >> More precisions:
> >> R version 2.13.1 (2011-07-08)
> >> Platform: x86_64-pc-linux-gnu (64-bit)
> >> metafor_1.6-0
> >
> >
> > Michael Dewey
> > info at aghmed.fsnet.co.uk
> > http://www.aghmed.fsnet.co.uk/home.html
> >

Michael Dewey
info at aghmed.fsnet.co.uk
http://www.aghmed.fsnet.co.uk/home.html