st: xtmelogit question

[Jennifer Manuel <jm703@columbia.edu>]

Hi,

I am estimating a mixed-effects logistic regression model using 
xtmelogit. I'm examining the impact of two case management models on 
medication adherence among 198 individuals who were followed over a 
3-year period. In estimating the model, I am getting the message 
"initial values not feasible" r(1400). The output is below. I've 
searched the listserv and have tried to use starting values from a 
simpler model using the from() option, but I still get the same error 
message. I would be grateful for any advice on what I'm doing wrong.

. xtmelogit nonadherencemo interval trtcond txBYintvl || id: interval, 
cov(un) var

Refining starting values:

initial values not feasible
r(1400);

Thank you,
Jennifer

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