If the privacy setting of my opt in question is set to "pseudonym" can I still identify a participant by their email adress?

Question

In my study participants must enter their email adress first, in a double opt-in procedure, to receive a link via email to access the questionnaire.

I know that using this method the email adresses are stored in a seperate database from the answers and I also know that by selecting pseudonym in the privicy section, participants gen an ID number in the database that stores the email adresses and a SERIAL code, in the database that stores the answers.

I want to know if, lets say, a participant asks for their data to be removed from the set (before the statistical analisis) I, as the admin of the questionnaire, can actually match their ID to their SERIAL and detele their answers.

I am asking this because I need to explain if this is a possibility to my ethics commitee.

Thank you!

Answer 1

No you can not, but the DPA that you have (or will) agreed to grants you the right to contact us as the service provider to take care of such a deletion.

Please take note, that this is typically a rare case. However, should there be a large number of such deletion requests, we may account the additional efforts.