Hi,
In my case, when there was no patient in the study population (even though there are someone in the target/comparator cohorts), that error occurred.
I recommend that you try to review your error log or the analysisSummary file which contains the information on the number of T / C / O.
For example, in my study package, there were T/C/Os and the analysisSettings like below.
T: Aripiprazole user with a previous tic disorder
C: Risperidone user with a previous tic disorder
O: tic disorder
PopulationSettings: “removeSubjectsWithPriorOutcome”: true
As a result, the number of each group in the study population was 0 and same error occurred like below.
I tracked the log file and found that the balance file (bal_txxx_cxxx_oxxx.rds) for that analysis wasn’t created. I removed that T-C-O pair in the study package, and the error disappeared.
Best,
Chungsoo