Can I calculate Cohen's d on z scores?


New Member
Hi everyone,

I am trying to calculate the size of the difference between the means of two groups in a psychological test. However, I am not using my own data but those published in an article and authors do report test performance in Z scores. Therefore, I am wondering whether or not I can just apply the regular formula of Cohen's d to calculate the size of the observed difference.

Thanks in advance for any possible help