I am using the package Metafor in R to do a meta-analysis, my models are derived from lmer (lme4). I am using the package -> EMAtools -> lme.dscore to retrieve the Cohen's d values which will be used in the meta-analysis.
What I am really stuck on is the variance for Cohen's d.
Last time we did this, we did the standard error to the power to 2 (SE^2) and that was sufficient to be considered the variance, however I am finding it difficult to find a citation as to how this would be considered correct.