In our study (already locked), we found an issue where the same subject has been assigned two different USUBJIDs — one at screening and another at rescreening.
This creates challenges because:
Normally, each subject should have only one unique USUBJID across the study.
Simply replacing the earlier USUBJID with the rescreened one could cause problems, since some datasets may have flags or derivations tied to SUBJID/USUBJID.
Domains like DS, SE, and SV are especially affected.
At the output level, the impact is minimal — it only affects disposition screen counts and screen failure counts.
Our question: Is it acceptable to leave ADaM and SDTM datasets as-is (with the duplicate USUBJID issue) and instead address this only in the disposition output? We could then provide an explanation of this approach in the Reviewer’s Guide for transparency.
Has anyone encountered a similar issue before? If so, how did you resolve it?
Any advice or examples would be greatly appreciated.
