Hi listers,
I have data for a a small clustered randomised trial comparing two treatments. The outcome is binary (side effects: yes/no) and quite rare for one of the treatments (8% incidence vs. 17% for the other treatment) so much so that in some centres (clusters), none of the patients had side effects.
I was planning to use -xtlogit- but it does not converge. I am not sure what test to use instead - should I opt for Poisson regression -xtpoisson- with robust SE assuming it is a good approximation? I am not sure if I can run a penalised maximum likelihood logistic regression using mixed models or is there any correction that can be made within the -xtlogit- options?
xtset clusters
xtlogit success i.intervention
I have data for a a small clustered randomised trial comparing two treatments. The outcome is binary (side effects: yes/no) and quite rare for one of the treatments (8% incidence vs. 17% for the other treatment) so much so that in some centres (clusters), none of the patients had side effects.
I was planning to use -xtlogit- but it does not converge. I am not sure what test to use instead - should I opt for Poisson regression -xtpoisson- with robust SE assuming it is a good approximation? I am not sure if I can run a penalised maximum likelihood logistic regression using mixed models or is there any correction that can be made within the -xtlogit- options?
xtset clusters
xtlogit success i.intervention
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