Hello,

I have difficulties with performing a meta-analysis. I have run a meta-analysis with risk ratios with built-in meta and with older package 'metan'. The results are different. I use random-effects model with DerSimonian-Laird to estimate between-study variance in both strategies. Here are my scripts:

1) 'metan' package:

meta summarize, random(dlaird) invvariance
gen lnor = ln(RR)
gen lnuci = ln(Upperlimit95)
gen lnlci = ln(Lowerlimit95)
metan lnor lnlci lnuci, eform effect(RR) random lcols(Publication)

2) built-in meta-analysis in Stata 16.0

meta set RR SE, random(dlaird) studylabel(Publication) studysize(Nsize)
meta summarize, random(dlaird)

(if I use lnRR and lnSE, stata does not perform the analysis because the values aren't positive)

I can see from the results that the weights are different.

If I run the built-in meta-analysis with e^RR and e^SE, the pooled estimate is bearly the same but confidence intervals very large with very different weights for each study.

So my question is: which result is the right? And how can I perform built-in meta-analysis in Stata 16.0 with risk ratios in the right way? I can't find any examples from Stata guides.