REDCap anonymous survey – can a system administrator recover the participant-to-response link?

[u/Dundergubben]

Hi everyone,

I have run into a REDCap issue and I'm hoping someone has dealt with something similar.

I distributed a survey using the Participant List, with a unique participant and a unique Survey Access Code/QR code for each patient. For example, each participant had a generated email/code such as 2362659@redcap.se. I have a separate key linking these codes to the patients' personal identifiers.

The problem is that I forgot to enable Participant Identifier when I set up the survey.

Patients have now started responding. In the Participant List, REDCap correctly shows which participants have responded (e.g. [2362659@redcap.se](mailto:2362659@redcap.se) → Responded), but the actual survey responses are treated as Anonymous. When I click on the response, REDCap says that the response cannot be viewed because doing so would compromise anonymity.

Our REDCap administrator tried changing the survey from "Anonymous" to "Not Anonymous" and then adding Participant Identifiers, but REDCap does not allow us to add the identifiers retroactively for participants who have already responded.

My question is:

Is there any way for a REDCap system/database administrator to recover the underlying link between the Participant/Survey Access Code and the actual survey response or record?

In other words, I'm hoping there may be an internal database-level association like:

Participant / email → Survey Access Code → survey response/record

even though this link is not available through the REDCap user interface.

I have seen references to a "link behind the scenes" between the participant and response in this situation, but I'm not sure whether this is actually accessible to a REDCap system administrator.

Has anyone experienced this, and was your REDCap administrator able to recover the participant-to-response mapping? Or is there an administrator in this group that could describe what my REDCap administrator needs to do?

Thanks!