I am in the process of conducting a meta-analysis. I am having difficulty replicating effect sizes that are in previous meta-analyses on the same topic. That is, for a given study I am not getting the same effect size estimate.
In these past meta-analyses, effect sizes and p-values are provided. Is it possible to use these estimates to obtain the variance of the effect size. For example, can I use the p-value and effect size to obtain the 95 % confidence interval, through which I can obtain the standard error.
As an aside, I have reached out to the authors of the previous meta-analyses and they have not responded.