Hello,
Â
I would like to do a meta-analysis with the package « metafor ». Ideally I
would like to use a mixed model because Iâm interested to see the effect of
some moderators. But the data set I managed to collect from literature presents
two limits.
Â
-Â Â Â Â Â Â Â Â Firstly, for each observation, I have means for a treatment
and for a control, but I donât always have corresponding standard deviations
(52 of a total of 93 observations donât 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 ».
-Â Â Â Â Â Â Â Â 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 ? Â
Â
Thank you for your help,
Â
Ãmilie.
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