Re: st: Meta-analysis questions

["Tiago V. Pereira" <tiago.pereira@mbe.bio.br>]

In practice, as long as the studies to be combined are not very small, I
believe that both random and randomi approaches will give virtually
identical results.

 If you are using data based on logor/selogor, I guess -metan- uses
automatically randomi (or fixedi) even if you specify fixed/random.

Cheers!

Tiago



> Dear Rui,
>
> 1) Yes, the default is the fixed-effect inverse variance method if your
> data is based on logor and selogor; typing "metan logor selogor, randomi"
> will give you the DerSimonian-Laird method.
>
> Type
>
> help metan
>
> to see the options.
>
>
> 2) As the message says, the option begg can handle only raw data (e.g. 2x2
> tables, with a b c d counts)
>
> Type
>
> help metabias
>
> for further information
>
>
> 3) You need to provide more information on your data set, and how the
> typename variable was coded.
>
> Also, try the pdfs that the following link shows :
>
> http://tinyurl.com/342osna
>
>
> Hope this helps.
>
> Tiago
>
>
> --------------
>
> Hi. I'm a new user of STATA and the meta-analysis commands and have a
> couple of questions...
>
> 1) For "metan logor selogor" command, is the default fixed effect? and
> if I would like to test for the DerSimonian & Laird random effects is
> it correct to type "metan logor selogor, random"?
>
> 2) I'm trying to do the command "metabias logor selogor, graph (begg)"
> but is giving me the following error message:
> Note: data input format theta se_theta assumed.
> Only Egger or Begg tests can be used with two input variables theta
> se_theta
> r(198);
>
> What is causing this and how should I resolve it?
>
> 3) I'm trying to do the command "metafunnel logor selogor, by
> (typename)" where typename is the type of different study designs but
> is it giving me the following error message:
> Note: default data input format (theta, se_theta) assumed.
> type mismatch
> r(109);
>
> If i don't put in "by (typename)" it works fine and giving me the
> funnel plot. What is causing this and how should I resolve it?
>
> Thank you so much in advance for your guidance.
>
> Rui
>
>


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