For an assignment (M.Sc. Epidemiology), I need to calculate a C.I. on a standardized risk difference (RD). To be more precise, I have 2 dichotomous variables, age (younger/older) and gender (m/f), thus yielding 4 stratum-specific RD estimates as regards to a certain exposure and outcome.
Any hints on how to do this would be appreciated (either mathematically or through an existing function in R -- I haven't found any in R's common epi packages).