Hi Yi,
Please look at description of AD0329 rule: "Within a Study and a Parameter, all BASECATy (Baseline Category y) variable values must be the same for each unique value of BASECAyN (Baseline Category y (N)), when primary variable BASECATy is populated"
It means that in your BDS dataset, there are records with the same values for PARAMCD and BASECA1N, but different values for BASECAT1 variable.
BASEC variable is not involved in algorithm of AD0329 validation rule.
Kind Regards,
Sergiy