ErroneousElement and DataExpected

The ErroneousElement and DataExpected elements should be populated in every RCSUM that reports an error.

These elements enable the recipient to identify precisely where the issue occurred within the message and understand what data was expected instead. Providing this detail supports more efficient internal processing, facilitates faster resolution of data issues, and helps prevent unnecessary repeated RCSUM generation.

Both elements are simple string data types. To promote consistency across systems and reduce the need for custom interpretation or mapping, it is recommended that senders follow the naming conventions and examples provided in the latest RDx validation rule documentation available here (access limited to RDx members).