pseudonymiserad

Pseudonymiserad describes data that has undergone pseudonymisation, a data processing technique in which identifying attributes are replaced with pseudonyms or tokens. The result is data that can still be analyzed and processed for secondary purposes, but the direct link to an individual is not readily visible without access to additional information, such as a separate key or mapping.

The primary purpose of pseudonymisation is to reduce identifiability and enhance privacy while preserving data utility for analytics, research, and service improvement. Pseudonymised data is commonly used in healthcare, finance, and technology sectors to enable data sharing and processing under regulatory requirements. However, because the re-identification of individuals remains possible with the appropriate key or auxiliary data, pseudonymised data is still considered personal data under many privacy frameworks, such as the GDPR.

Typical methods include tokenization (replacing identifiers with tokens), reversible encryption or hashing with a secret salt, and selective masking of sensitive fields. The choice of method depends on the data’s use case, the required reversibility, and the risk tolerance of the processing entity. Proper pseudonymisation relies on robust key management, access controls, and auditability to prevent unauthorized re-identification.

Ethical and legal considerations emphasize that pseudonymised data should be protected by security safeguards and used in accordance with data protection principles. While pseudonymised data reduces risk, it does not eliminate the obligation to protect personal data or to justify processing purposes and legal bases.