st: Time-splitting problem

[Morten Støver <morten.stover@ntnu.no>]

I'm doing an analysis where I want to split up the follow up-time in 
three parts. So my original model is like this:
xi: xtmelogit up KJONN dev_lag1 year_92 year_92_kv, || bosted:, 
covariance(independent) || year:, covariance(independent) or variance
My time-variable is year_92 and goes from 0 to 15, and I guess the code 
(for the first part) should be
if year_92==0 | year_92==1 | year_92==2 | year_92==3 | year_92==4 | 
year_92==5
My problem is that I really don't know where to put it, and whatever I 
try, I get "option if not allowed r(198);"
I am using Stata10

Thanks for any help

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