I am performing a sample size calculation in G*Power for a logistic regression with continuous predictor. I am requested to estimate a value for Pr(Y=1 | X=1) H0, i.e. the probability that my binary outcome (group) =1, when my main predictor is at its mean, and to estimate a value for Pr(Y=1 | X=1)H1, i.e. the probability that my binary outcome (group) =1, when my main predictor is one SD unit above its mean.
The paper I am extracting the estimates from reports means and SDs of the two groups (which are my predicted variable). How can I estimate the probability values requested by G*Power?