Hello,

I am trying to determine the power of one my analyses. The outcome is binary and relative risk if the effect estimate, determined using a modified Poisson regression with robust error variance. The exposure variable is categorical and has 5 groups (placebo with 4 levels of treatment). I am struggling on how to determine the power, or which options to choose in STATA, for this aim given the 5 levels of exposure. I was wondering if anyone could provide some assistance on how to proceed with this power analysis in STATA? Thanks!