I am doing a meta-analysis using PLINK.
I have the *.assoc files for each study and I have used the
--meta-analysis + qt study weighted-z options.
I have the following questions in order to do a forest plot:
1) I need the beta and SE of the meta-analysis. PLINK provides a BETA (fixed model), but not the SE. How do I compute it? I would thought I would get one, but otherwise should I use:
SE = SQRT ( 1/ SUM weights)
Where the weights = the inverse variance
2) I also need the beta and corresponding SE of each study for the forest plot. However, when I check the indvidual *.assoc files and the last columns on the *.meta files, the betas are different. Why?