Hello everyone. I am trying to get a confidence interval for the risk ratio (vaccinates/control) from the following model: fit.1<-glm(sick~trt + loc, data=b, family=binomial). here trt is one for vaccinates and 0 for control, loc is a binary (1/0) variable. I am trying to get a reference to apply the delta method to get my CI. Any ideal? ******************************************* Antonio Paredes USDA- Center for Veterinary Biologics Biometrics Unit 510 South 17th Street, Suite 104 Ames, IA 50010 (515) 232-5785 [[alternative HTML version deleted]]