[R-meta] Calculating standard errors from confidence interval and weights assigned

[Michael Dewey]

Dear Win

If you fit a random-effects model then the weights become more nearly 
equal tending to equality as tau^2 increases. I suspect that may be the 
issue here.

Michael

On 12/07/2023 05:36, Win Thu via R-sig-meta-analysis wrote:
> Hello,
> 
> I would like to seek your opinions on calculating standard error (sei) 
> from confidence intervals, and weights assigned to each study in a 
> random effects model.
> To include in rma function*rma(yi, sei, data)*, I used the following 
> formula to calculate sei
> 
> *sei <- [log(CI upper limit) - log(CI lower limit)] / 3.92 *
> For yi, it will be log(relative risk).
> 
> Then, I have the following weights for each study, which I am not very 
> confident as the studies with larger sample sizes (cohort studies) were 
> given reduced weights compared to smaller studies (case-control).
> I need to combine both studies as there are limited studies on the topic.
> 
> I am grateful for your feedback.
> 
> Untitled.png
> Thank you,
> Win
> 
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-- 
Michael
http://www.dewey.myzen.co.uk/home.html