Averaging cohen d

Hi everyone,
I have performed a study comparing the means of two groups (placebo vs. control) in a set of dependent variables. I have performed this comparison using raw (uncorrected data) and different corrections. Some of the observed differences vary depending on which correction was applied, whether others are repeatedly observed (regardless of which correction was applied). I would like to summarize the later and provide an estimation of the effect size. Therefore, for each dependent variable, I averaged the cohen's d values obtained with the different methods. However, I am not sure if that's correct and, if it is, I do not know how to proceed to obtain a 95% Confidence Interval for this average. Could anyone help me?
Thanks in advance for any suggestion.