Resetting retained values with by variables

OPHD1 — Mon, 05 May 2014 16:45:52 GMT

I have a longitudinal data set with rows for a member||visit. I am interested in creating flag by each memberid. In particular, I am looking to create a new flag (flag2) that is based on a certain value of flag1 (in sample data set). I want flag2 to be 1 the first time it sees flag1 = 3 and then kept at 1 for all remaining records for the same memberid. E.G. there may be values other than 3 in subsequent visits for that member, but I still want that member to have flag2 = 1 since it is a record after the first value of flag1 = 3. I've tried using various iterations of retain, sum, etc. and am not having any luck. Would appreciate any thoughts. Please see data below:

data test;

input memberid visit flag1;

datalines;

123 1 0

123 2 0

123 3 1

123 4 0

123 6 3

456 1 3

456 2 7

456 3 0

789 1 0

789 2 1

789 3 2

789 4 0

789 5 3

789 6 0

;

run;

proc sort data=test;

by memberid;

run;

data test2;

set test;

by memberid ;

flag2 = (flag1 = 3);

*but also want for all subsequent observations for that member;

run;

So the data set I want is:

memberid visit flag1 flag2

123 1 0 0

123 2 0 0

123 3 1 0

123 4 0 0

123 6 3 1

456 1 3 1

456 2 7 1

456 3 0 1

789 1 0 0

789 2 1 0

789 3 2 0

789 4 0 0

789 5 3 1

789 6 0 1

Re: Resetting retained values with by variables

ballardw — Mon, 05 May 2014 16:49:42 GMT

data test2;

set test;

by memberid ;

retain flag2;

if first.memberid then flag2 = (flag1 = 3);

*but also want for all subsequent observations for that member;

run;

should do it.

Re: Resetting retained values with by variables

Reeza — Mon, 05 May 2014 16:53:05 GMT

Would flag2 ever reset if its only checking on first.memberid?

data test2;

set test;

by memberid ;

retain flag2;

if first.memberid then flag2=.;

flag2 = max((flag1 = 3), flag2);

*but also want for all subsequent observations for that member;

run;

Re: Resetting retained values with by variables

OPHD1 — Mon, 05 May 2014 16:58:12 GMT

Thanks very much. The max function with the logic as input is clever. Appreciate both your responses.

topic Resetting retained values with by variables in SAS Procedures

Resetting retained values with by variables

Re: Resetting retained values with by variables

Re: Resetting retained values with by variables

Re: Resetting retained values with by variables