I have been trying to use the first/last commands for the last hour and trying to figure out how to get this to work.
I have the following sample lab data:
id | date | count | year |
1 | 12/5/2007 | < 75 | 2007 |
1 | 2/27/2008 | 500 | 2008 |
1 | 6/30/2008 | < 75 | 2008 |
1 | 10/27/2008 | < 75 | 2008 |
1 | 2/23/2009 | 900 | 2009 |
1 | 6/1/2009 | < 75 | 2009 |
1 | 8/24/2009 | < 75 | 2009 |
1 | 12/7/2009 | < 75 | 2009 |
2 | 4/25/2007 | 77 | 2007 |
2 | 7/6/2007 | < 75 | 2007 |
2 | 8/27/2007 | < 75 | 2007 |
2 | 11/26/2007 | < 75 | 2007 |
2 | 1/28/2008 | < 75 | 2008 |
2 | 6/30/2008 | < 75 | 2008 |
2 | 11/5/2008 | < 75 | 2008 |
2 | 2/9/2009 | < 75 | 2009 |
2 | 5/11/2009 | < 75 | 2009 |
2 | 9/23/2009 | < 75 | 2009 |
2 | 3/1/2010 | < 75 | 2010 |
So as you noticed, each person may have multiple labs per year. I want to grab the first lab (by date) for each year for each person. So basically I want a table that looks like this:
id | date | count | year |
1 | 12/5/2007 | < 75 | 2007 |
1 | 2/27/2008 | 500 | 2008 |
1 | 2/23/2009 | 900 | 2009 |
2 | 4/25/2007 | 77 | 2007 |
2 | 1/28/2008 | < 75 | 2008 |
2 | 2/9/2009 | < 75 | 2009 |
2 | 3/1/2010 | < 75 | 2010 |
So far, I have tried sorting it by ID and date created a dataset using first.date; but that didn't work.
I was wondering if someone can provide me with some help? I am pretty lost on how to do this!
Thanks!
It's FIRST.YEAR that must be used, you want the first record (date) within each year :
proc sort data=sample; by id year date; run;
data want;
set sample; by id year;
if first.year;
run;
PG
It's FIRST.YEAR that must be used, you want the first record (date) within each year :
proc sort data=sample; by id year date; run;
data want;
set sample; by id year;
if first.year;
run;
PG
Are you ready for the spotlight? We're accepting content ideas for SAS Innovate 2025 to be held May 6-9 in Orlando, FL. The call is open until September 25. Read more here about why you should contribute and what is in it for you!
Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
Find more tutorials on the SAS Users YouTube channel.