Create study day variable for multiple per day encounters

[he2182]

Hi,

I am trying to create a study day variable for patients that have multiple encounters per day.

For example:

ID    Date        Study Day (want to create this)

12   6/20/14      1

12   6/20/14      1

12   6/20/14      1

12   6/20/14      1

12   6/22/14      2

12   6/26/14      3

13   6/20/14      1

Any thoughts?

Thanks!

[Miracle · Accepted solution]

Hi, perhaps you could try this?

data have;

input ID DATE MMDDYY10.;

datalines;

12   6/20/14

12   6/20/14

12   6/20/14

12   6/20/14

12   6/22/14

12   6/26/14

13   6/20/14

;

run;

proc sort data=have; by ID Date; run;

data want;

  set have;

  by ID Date;

  if first.id then studyday=.;

  if not missing(date) then do;

  if date ne lag(date) then studyday+1;

  end;

run;

proc print noobs; format date ddmmyy10.; run;

[Reeza]

Data want;

set have;

by id date;

retain studyday;

if first.id the studyday=0;

if first.date then studyday+1;

run;

[he2182]

Thank you both so much! The solutions worked perfectly!