Date:         Mon, 27 Aug 2007 14:58:10 -0500
Reply-To:     Mary <mlhoward@avalon.net>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Mary <mlhoward@AVALON.NET>
Subject:      Re: How to count in sub-sets of a continuous variable?
Comments: To: Haris <Karovaldas@GMAIL.COM>
Content-Type: text/plain; charset="iso-8859-1"

Haris,

Is each row a patient visit?  There is a group by statement in Proc SQL that you might try; I'm not sure if it will work on these multiple counts

select id,  count(*) as count
   from table
   group by id;

If that doesnt work, you could select the distinct ID's and then select ID's and counts individually like this above, then merge them to your id's one by one.

-Mary 
  ----- Original Message ----- 
  From: Haris 
  To: SAS-L@LISTSERV.UGA.EDU 
  Sent: Monday, August 27, 2007 10:16 AM
  Subject: How to count in sub-sets of a continuous variable?


  I have a dataset with multiple rows per ID.  Each of the rows has a
  unique time stamp.  I want to count how many ID's have data within
  certain time windows.  Here's a code that counts the number of rows in
  each time-window.

  proc sql ;
          title 'N of Patients and Visits during FU by Procedure' ;
          select  count('CTU-ID'n)                         label='Total Visits',
                  count (unique 'CTU-ID'n)                label='Total Patients',
                  sum(Days LE 30)                         label='Visits within 30 Days',
                  sum(Days between 31 and 90)      label='Visits 31 to 90 Days',
                  sum(Days between 91 and 180)    label='Visits 91 to 180 Days',
                  sum(Days between 181 and 270)   label='Visits 181 to 270 Days',
                  sum(Days GT 270)                       label='Visits 270+ Days'
          from AFLee.Merged ;
  quit ; title ;

  How do I make it count not rows, but unique IDs within those windows?

  Thanks.