Date:         Wed, 30 Jul 2003 14:57:21 +0200
Reply-To:     "Laproi, L.G.E (Louis)" <louis.laproi@HOOGEHUYS.NL>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "Laproi, L.G.E (Louis)" <louis.laproi@HOOGEHUYS.NL>
Subject:      Re: HELP - Data Manipulation
Comments: To: Ellen <erains@NERI.ORG>
Content-Type: text/plain; charset="WINDOWS-1252"

Ellen,
this seems to work on your example.
BTW what happens when a patient tick 3 the first time?

cull




DATA visit;

INPUT ID   Visit $ Var1;

CARDS;
10001        6M             2
10001        12m            2
10001        24m            3
10001        36m            1
10001        60m            3
10002        1m             1
10002        12m            3
10002        36m            3
10002        48m            2
10002        60m            3
RUN;

DATA visit2;
   SET visit;

   BY ID;
   * store last observation init 0;
   RETAIN before 0;

   * newvar1 only to clarify;
   IF var1 EQ 3 THEN
      newvar1 = before;
   ELSE
      newvar1 = var1;

   * update only when useful;
   IF var1 NE 3 THEN
      before = var1;

   RUN;


proc print; run;

-----Oorspronkelijk bericht-----
Van: Ellen [mailto:erains@NERI.ORG]
Verzonden: woensdag 30 juli 2003 14:26
Aan: SAS-L@LISTSERV.UGA.EDU
Onderwerp: HELP - Data Manipulation


I have a variable that is coded 1 = Yes 2 = No and 3 = Unchanged from last
visit.  I need to be able to convert all the "3" to "Yes" or "No" based on
the last visit the variable was recorded as a 'Yes" or "No". A patient may
have several "Unchanged from last visit" interspersed in with Yes and No
answers and for each instance I have to look for the last Yes, No answer
given. See data below:

ID           Visit         Var1
10001        6M             2
10001        12m            2
10001        24m            3
10001        36m            1
10001        60m            3
10002        1m             1
10002        12m            3
10002        36m            3
10002        48m            2
10002        60m            3


Any thoughts? Thanks


**********************************************************************
Dit e-mailbericht is alleen bestemd voor de geadresseerde(n).
Gebruik door anderen is niet toegestaan. Indien u niet de"
geadresseerde(n) bent wordt u verzocht de verzender hiervan
op de hoogte te stellen en het bericht te verwijderen.
Door de elektronische verzending kunnen aan de inhoud van
dit bericht geen rechten worden ontleend.
**********************************************************************
This e-mail message is intended to be exclusively for the addressee.
If you are not the intended recipient you are kindly requested not to
make any use whatsoever of the contents and to notify the sender
immediately by returning this e-mail message. No rights can be
derived from this message.
**********************************************************************