I have a dataset (patients) as such:
Pat_ID Hos Date
A 11 1/1/2012
B 12 2/3/2012
B 13 2/3/2012
C 11 4/1/2012
C 11 4/5/2012
How do I count using proc sql such that the outcome looks something like this:
Pat_ID Visits
A 1
B 1
C 2
Since B has two visits on the same date, they are considered as only 1 visit, whereas C has 2 visits because they are on different dates.
you can try:
proc sql;
select pat_id, count(distinct date) as visits
from patients
group by pat_id;
quit;
you can try:
proc sql;
select pat_id, count(distinct date) as visits
from patients
group by pat_id;
quit;
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