You can protect the privacy of your study subjects by:
Researchers aiming to store personal data on human subjects should consider involving a trusted third party (ttp) to encrypt and decrypt identifiers. This is not legally required, but it could enhance the trust of the general public that all feasible measures were taken to protect the privacy of the study subjects.
Strictly speaking, a mere encryption is sufficient. When also allowing decryption of encrypted data, processes should be in place to limit such decryption rights to people for whom a legal ground exists to have access to such knowledge. Such processes can either be guaranteed by standard operation procedures and risk assessments within the organisation itself or by involving a TTP.
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