incidence rate ratio

  1. P

    Should IRRs and HRs always be equal?

    I am running an analysis in a large population registry where individuals enter and leave the dataset at different time points. When i estimated the IRR between two distinct groups and a health outcome, and then a HR, I am finding a small difference (IRR 2.18, HR 2.01). Shouldn't they have...
  2. W

    Do I need this variable in the class statement? And IRRs

    I am trying to calculate incidence rate ratios and 95% CIs for the interaction between two variables: area and time. My variables are n, area, period, and age (using log of population as the offset). I have two questions that tie together for the code I am using, which is: proc genmod...