Estimate of Crude Event Rate w/out Regression Model

[byrne410]

I am looking to compare my output for a treatment effect in a regression model to an estimate of crude event rate obtained without using a regression model. The regression model is not causing any difficulties, but my other model is. I want to compute my total number of events and the follow-up time for each of my treatment groups so that I can provide a crude event rate for each of my treatment groups, but thus far I have not been able to achieve this. I assumed I could use a proc freq procedure:

[Reeza]

How would you calculate this by hand?

Its easiest if you post sample data (not necessarily actual data) with the desired output format/calculation.

For time based analysis I'm assuming you're using proc phreg? or proc lifereg?

[byrne410]

To calculate it by hand, I would only need a summary of the overall incidence between my treatment groups. Then I could provide a estimate of the crude event rate for each group.  My data would look similar to this, except there will be many more observations:

Id     trtgrp     nevents      followuptime

1     1          3                    5

2     1          4                    6

3     1          3                    4  

4     0          5                    5

5     0          7                    5

6     0          6                    5

7     0          6                    4

[Reeza]

What would the output be for this particular data example?

I'm just confused with an ID and the the nevents being 3, indicates multiple events per ID?