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Hi,
I'm struggling with my data...
I have a file with multiple records for certain persons. If a person (person A) has scored 1 for a certain variable (event) the records hereafter, which are sorted by date, should also score 1.
How do I do that?
AnnieLin

This may do:

thanks for that , but it didn't really work. It gives a "1" in the record where event001=1 and the next one.
It should be in all the next lines with the same PATCOD (not necessarily where Event001=1)
I'm not familiar with the command LAG(variable), I should educate myself...Is there a clear explanation available for this on the net?
What I've done in the mean time is very complex and prone to mistakes (see below) . Can you see an obvious mistake?

*restructurate.
SORT CASES BY PATCOD Birthdate .
CASESTOVARS
/ID=PATCOD Birthdate
/GROUPBY=VARIABLE.

*than computed a new variabel
COMPUTE PREV0adm1=0.
compute prev1adm2=EVENT001.1.
COMPUTE PREV2adm3=EVENT001.1 + EVENT001.2.
COMPUTE PREV3adm4=EVENT001.1 + EVENT001.2 +EVENT001.3.
etc

*than restructurated it back
VARSTOCASES
/MAKE PREVV FROM PREV0adm1 prev1adm2 PREV2adm3 PREV3adm4
/INDEX=Index1(4)
/KEEP=PATCOD
/NULL=DROP
/COUNT=casenr.

RECODE PREVV (0=0) (1 thru Highest=1) INTO Pr_event.
EXECUTE.

Oh, sorry. I made a mistake. Try this one:



LAG is a function to borrow the data in the previous row.

See this syntax:
IF patcod = lag(patcod) and lag(eventrecoded) = 1 eventrecoded = lag(eventrecoded) .

Literally, it means if patcod on any row k is equal to patcod on row (k-1) AND the eventrecoded in the previous row is 1, then recode the eventrecoded in row k as 1.

Thanks, I understand better now. It still didn't do exactly what I wanted, but I rewrote the syntax to the one below and now it seems to do the trick.
In the previous one, also alle events without a previous event were scored 1, which they shouldn't.
Thanks for your help!

* Make a new variable .
COMPUTE eventrecoded = 0 .
EXECUTE .

* Recode into a chain of 1 if event has already occurred .
IF patcod = lag(patcod) and lag(event001) = 1 eventrecoded = 1.
EXECUTE .
IF patcod = lag(patcod) and lag(eventrecoded) = 1 eventrecoded = 1.
EXECUTE .

That's probably because I didn't understand the request correctly. I am glad that the problem was rectified.