I have the following data. I sorted it by ID and date. How can I get the first date for each patient but if there is a missing value in the location column, I want the next non-missing value?
data fake_data;
input patID $ date monyy6. location $ outcome ;
format date monyy.;
datalines;
1693 Dec-14 . 1
1693 Nov-14 . 1
1693 Oct-14 CA 1
1693 Sep-14 CA 0
1693 Aug-14 CO 0
1693 Jul-14 CO 0
1129 Feb-18 . 1
1129 Jan-18 . 0
1129 Dec-17 NY 0
1129 Nov-17 PA 0
1345 Jun-19 . 0
1345 May-19 . 0
1345 Apr-19 NY 0
1345 Mar-19 NY 0
1345 Feb-19 NY 0
1345 Jan-19 CA 0
1345 Dec-18 CA 0
1345 Nov-18 CA 0
;
I have this so far...
proc sql;
create table test as
select A.*,
coalesce(A.location, B.location) AS location_2
from fake_data A, fake_data B
where A.patID = B.patID
group by A.patID
order by A.patID, A.date desc;
quit;
I would like to be able to sort it so that I can choose the first entry which will have all columns with data.
I wanted not missing location but all the date and outcome data have to come from the most recent date. I am interested in the data with most recent date and backfilling location. But I found the solution if anyone comes across this...
data fake_data; input patID $ date monyy6. location $ outcome ; format date monyy.; datalines; 1693 Dec-14 . 1 1693 Nov-14 . 1 1693 Oct-14 CA 0 1693 Sep-14 CA 0 1693 Aug-14 CO 0 1693 Jul-14 CO 0 1129 Feb-18 . 1 1129 Jan-18 . 0 1129 Dec-17 NY 0 1129 Nov-17 PA 0 1345 Jun-19 . 0 1345 May-19 . 0 1345 Apr-19 NY 0 1345 Mar-19 NY 0 1345 Feb-19 NY 0 1345 Jan-19 CA 0 1345 Dec-18 CA 0 1345 Nov-18 CA 0 ; proc sort data=fake_data; by patID descending date; run; data fake_row; set fake_data; rownum=_n_; run; proc sql; create table test as select A.*, B.rownum as rownum2, coalesce(A.location, B.location) AS location_2 from fake_row A, fake_row B where A.patID = B.patID group by A.patID order by A.patID, A.date desc; quit; data test2; set test; where not missing(location_2); row = rownum + rownum2; run; proc sort data=test2; by patID row; run; data final; set test2; by patID row; if first.patID; run;
It is not clear what you expect as result.
If you just want the first obs with non-missing location for each id, then try:
data want;
set fake_data;
by patID notsorted; /* EDIT: Your data is grouped by id, but not sorted */
where not missing(location);
if first.patID;
run;
I wanted not missing location but all the date and outcome data have to come from the most recent date. I am interested in the data with most recent date and backfilling location. But I found the solution if anyone comes across this...
data fake_data; input patID $ date monyy6. location $ outcome ; format date monyy.; datalines; 1693 Dec-14 . 1 1693 Nov-14 . 1 1693 Oct-14 CA 0 1693 Sep-14 CA 0 1693 Aug-14 CO 0 1693 Jul-14 CO 0 1129 Feb-18 . 1 1129 Jan-18 . 0 1129 Dec-17 NY 0 1129 Nov-17 PA 0 1345 Jun-19 . 0 1345 May-19 . 0 1345 Apr-19 NY 0 1345 Mar-19 NY 0 1345 Feb-19 NY 0 1345 Jan-19 CA 0 1345 Dec-18 CA 0 1345 Nov-18 CA 0 ; proc sort data=fake_data; by patID descending date; run; data fake_row; set fake_data; rownum=_n_; run; proc sql; create table test as select A.*, B.rownum as rownum2, coalesce(A.location, B.location) AS location_2 from fake_row A, fake_row B where A.patID = B.patID group by A.patID order by A.patID, A.date desc; quit; data test2; set test; where not missing(location_2); row = rownum + rownum2; run; proc sort data=test2; by patID row; run; data final; set test2; by patID row; if first.patID; run;
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