topic Re: How to compute incidence rate and confidence interval in SAS Programming

How to compute incidence rate and confidence interval

jing2000yr — Wed, 09 Oct 2013 01:12:21 GMT

I have a dataset from a longitudinal study to compute incidence rate and the confidence interval.I need to compute the number of new cases(the number of the variable 'case'=1) divided by the sum of the total person-years.Need your kindly help on the coding.Thanks!

The example dataset is like

case pyr

1 3

0 5

1 3.4

0 5

1 2.1

0 5

Re: How to compute incidence rate and confidence interval

PGStats — Wed, 09 Oct 2013 01:51:36 GMT

Assuming you want to sum the pyr only for the new cases :

data have;
input ase    pyr;
datalines;
1          3
0          5
0         5
1         3.4
0         5
0        5
0        5
1       2.1
0       5
;

data want(keep=newCases sumPyr ratio);
do until(done);
     set have end=done;
     if ase then do;
          newCases + 1;
          sumPyr + pyr;
          end;
     end;

ratio = newCases / sumPyr;
run;

proc print data=want noobs; run;

Re: How to compute incidence rate and confidence interval

jing2000yr — Tue, 05 Nov 2013 16:08:01 GMT

Thanks!