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Difference between adjusted exponentiated means in proc genmod

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Difference between adjusted exponentiated means in proc genmod

Hello, 

I am trying to find the difference between adjusted exponentiated means using proc genmod. I have two sets of patients: 1 set took drug A (DrugA=1), 1 set did not (DrugA=0). The outcome is the total number of times they visited the doctor, so  count variable so I would like the distribution to be Poisson and the link to be log. Here is the code:

 

PROC genmod DATA=MYDATA;

CLASS covariate1 DRUGA/DESC;
model DocVisits=DrugA covariate1 covariate2 /link=log dist=poisson ;
lsmeans DrugA / exp diff cl ;
run;

 

And here is the output:

 

SAS Output

DrugA Least Squares Means
DrugA  Estimate Standard Error z Value Pr > |z| Alpha Lower Upper Exponentiated Exponentiated
Lower
Exponentiated
Upper
1 4.2798 0.01154 370.78 <.0001 0.05 4.2572 4.3024 72.2270 70.6113 73.8796
0 4.3194 0.009114 473.94 <.0001 0.05 4.3016 4.3373 75.1464 73.8160 76.5008

Differences of DrugA Least Squares Means
DrugA  DrugA  Estimate Standard Error z Value Pr > |z| Alpha Lower Upper Exponentiated Exponentiated
Lower
Exponentiated
Upper
1 0 -0.03963 0.01419 -2.79 0.0052 0.05 -0.06743 -0.01182 0.9611 0.9348

0.9883

So rather than see the difference "-0.03963" and its exponentiated estimate and confidence interval, I would like to see the difference between 75.1464 and 72.2270, 2.9194, and its confidence interval.  Is there a way to get this from SAS?
Thanks so much in advance for any advice!
 
 
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