topic Re: Assigning values to a variables based on recent visitnumber in SAS Programming

Assigning values to a variables based on recent visitnumber

knveraraju91 — Mon, 09 Jan 2017 05:21:27 GMT

Dear,

I need to assign values to a variable (avisitnum) based on recent visit when the visit is unscheduled.

Eg. For the OBS 4, the avisitnum value is 2 because recent scheduled visit is scheduled2 and visitnum=2.

For unscheduled visit, the recent visitnum should be populated

data

id period date visit visitnum
1 period1 2015-06-02 scheduled1 1
1 period1 2015-06-07 scheduled2 2
1 period1 2015-06-23 scheduled3 3
1 period1 2015-06-17 unscheduled 99

output needed

id period date visit visitnum avisitnum
1 period1 2015-06-02 scheduled1 1 1
1 period1 2015-06-07 scheduled2 2 2
1 period1 2015-06-23 scheduled3 3 3
1 period1 2015-06-17 unscheduled 99 2

Re: Assigning values to a variables based on recent visitnumber

Shmuel — Mon, 09 Jan 2017 06:00:03 GMT

Use:

proc sort data=have; by id period date; run;

data want;

set have;

prev_visitnum = lag(visitnum);

if visit = "unscheduled" then visitnum - prev_visitnum;

/* OR if visitnum=99 then visitnum = prev_visitnum */

drop prev_visitnum;

run;

Re: Assigning values to a variables based on recent visitnumber

mnjtrana — Mon, 09 Jan 2017 06:10:45 GMT

Hey,

you can use the below code to populate the recent visit on the unscheduled visits.

data have;
length date 8 visit $12;
informat date yymmdd10.;
input id $ period $ date $ visit $ visitnum ;
datalines;
1     period1    2015-06-02       scheduled1        1
1     period1     2015-06-07       scheduled2        2
1     period1     2015-06-23       scheduled3        3
1     period1     2015-06-17      unscheduled       99
run;

proc sort data = have;
by id period date visitnum;
run;


data need(drop=a);
set have;
format date ddmmyyd10.;
retain avisitnum;
by id period date visitnum;
a = avisitnum;
if first.period then avisitnum=1;
else avisitnum+1;
if visitnum=99 then avisitnum=a;
run;

hope this helps!

Manjeet

Re: Assigning values to a variables based on recent visitnumber

RW9 — Mon, 09 Jan 2017 10:25:35 GMT

Out of interest, what are you doing with avisitnum? It looks a bit like your creating ADaM datasets here, you may want to check the CDISC documentation, as it is AVISIT, AVISITN, and there are examples on populating unscheduleds. Its just if you keep that output, avisit looks duplicate.