[R] questions about "metafor" package

[Emilie MAILLARD]

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 deviations 
(52 of a total of 93 observations don’t have standard deviations). 
Nevertheless I have the sample sizes for all observations so I wonder if it was 
possible to weight observations by sample size in the package « metafor ».
-         Secondly, some observations are probably not independent as I 
have sometimes several relevant observations for a same design. More precisely, 
for these cases, the control mean is identical but treatment means varied. 
Ideally, I would not like to do a weighted average for these non-independent 
observations because these observations represent levels of a moderator. I know 
that the package « metafor » is not designed for the analysis of correlated 
outcomes. What are the dangers of using the package even if observations are 
not really independent ?  
 
Thank you for your help,
 
Émilie.
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