Hello all,

Situation: I'm running network meta-analysis and I have trials that have two arms that use the same vaccine. An example would be a trial with a control group, a "vaccine A" group, another "vaccine A" group, and a "vaccine B" group.

Problem: when I run the network setup command, I get an error message that indicates that my study variable and my treatment variable don't uniquely identify observations.

Question: Should I add the two groups of "vaccine A" together? that sounds like losing power, but do I have another option?

Code: network setup number_sick number_animals, studyvar (Study) trtvar (vaccine_) or

Error: variables Study vaccine_ do not uniquely identify the observations

Thank you,
Joaquin

Data (just as an example):
Study number_animals number_sick vaccine_
1 48 20 Control
1 48 16 A
1 48 16 A
1 126 1 B
2 107 1 Control
2 107 5 B
2 107 1 C
2 107 4 D