Message-ID: <Zen-1UkxFT-00029X-Ax@smarthost04.mail.zen.net.uk>
Date: 2013-06-07T14:02:36Z
From: Michael Dewey
Subject: Add prediction interval forest plot (package "meta")
In-Reply-To: <51B1C67B.1050801@uni-koeln.de>
At 12:39 07/06/2013, Bernd Wei? wrote:
>Am 07.06.2013 13:17, schrieb Michael Dewey:
>>At 19:34 06/06/2013, Bernd Weiss wrote:
>>>Dear all,
>>>
>>>I am struggling to add a prediction interval to a forest plot that was
>>>created with forest.meta(), package "meta".
>>>
>>>I checked the source of forest.meta() and realized that it is heavily
>>>relying on grid. I am lacking any experience with grid graphics. So, I
>>>am having difficulties to find out where the random effects estimate is
>>>actually plotted in order to add prediction intervals.
>>
>>I appreciate this is not a direct answer to your question but the
>>equivalent function in metafor (available from CRAN) does this and it
>>might be easier to use that.
>
>Thanks, Michael!
>
>Yes, I vaguely remember that the metafor package
>can calculate the PIs but most of our analyses
>rely on the meta package. On the other hand,
>this might be a good reason to finally switch to metafor.
>
>You probably refer to the function addpoly()
>which can be used for that. I will check it out.
I was thinking of the addcred parameter to
forest.rma.uni in fact, although you could roll your own.
>Again, thanks for your help,
>
>Bernd
Michael Dewey
info at aghmed.fsnet.co.uk
http://www.aghmed.fsnet.co.uk/home.html