[R-meta] aggregate data continues outcomes

[Viechtbauer, Wolfgang (SP)]

Dear Homa,

Please always cc the mailing list when replying.

This is a mailing list to discuss the use of *R* for conducting meta-analyses ...

Best,
Wolfgang 

>-----Original Message-----
>From: Homa Keshavarz [mailto:homa.keshavarz12 using gmail.com]
>Sent: Wednesday, 16 December, 2020 16:08
>To: Viechtbauer, Wolfgang (SP)
>Cc: Homa Keshavarz
>Subject: RE: [R-meta] aggregate data continues outcomes
>
>Dear Wolfgang,
>Thank you for answering my question.
>
>I need group B and C combine:
>Group A: mean =1248   Sd= 698  n=15
>Group B: mean =2381   Sd= 1313  n=15
>Group C: mean =1878   Sd= 720  n=15
>
>I do not use R. is there any other way e.g. SPSS or formula in excel please?
>
>I do appreciate your time,
>Homa
>
>-----Original Message-----
>From: Viechtbauer, Wolfgang (SP)
><wolfgang.viechtbauer using maastrichtuniversity.nl>
>Sent: Wednesday, December 16, 2020 2:06 AM
>To: Homa Keshavarz <homa.keshavarz12 using gmail.com>;
>r-sig-meta-analysis using r-project.org
>Subject: RE: [R-meta] aggregate data continues outcomes
>
>Dear Homa,
>
>Please post in plain text. Note how the formatting of the table is messed up
>when not doing so, making it difficult for people to read the table and
>provide help.
>
>It would also help if you would provide the table in a way that it can be
>directly generated within R (e.g., using dput()). See the following links
>for how to create reproducible examples:
>
>https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducib
>le-example
>http://adv-r.had.co.nz/Reproducibility.html
>https://cran.r-project.org/web/packages/reprex/vignettes/reprex-dos-and-dont
>s.html
>
>Not sure what effect size measure you intend to use. Standardized mean
>differences? If so, you will find an example and code that deals with this
>kind of data here:
>
>http://www.metafor-project.org/doku.php/analyses:gleser2009#quantitative_res
>ponse_variable
>
>In essence, you need to compute the var-cov matrix of the two effects and
>then you can combine them with rma.mv(). If you provide the table in such a
>way that it can be directly generated within R, I can help further.
>
>Best,
>Wolfgang
>
>>-----Original Message-----
>>From: R-sig-meta-analysis
>[mailto:r-sig-meta-analysis-bounces using r-project.org]
>>On Behalf Of Homa Keshavarz
>>Sent: Tuesday, 15 December, 2020 19:27
>>To: 'Röver, Christian'; r-sig-meta-analysis using r-project.org
>>Subject: [R-meta] aggregate data continues outcomes
>>
>>I do appreciate it if you direct me how to aggregate the 2 groups below.
>>This study has 3 arms, comparison between A , B, and C.
>>Group 1: A compare to B
>>Group 2: A compare to C
>>I need to aggregate theses 2 groups
>>
>>
>>	M	SD	N	M	DD	N
>>Group1	1248.0	698.0	15	2381.0	1313.0	15
>>Group2	1248.0	698.0	15	1878.0	720.0	15
>>
>>Many thanks in advance,
>>Homa