RespondentID

RespondentID is a unique identifier assigned to an individual who participates in a study, survey, or data collection project. It is designed to be stable across data collection events and to enable linkage of responses without revealing the respondent's identity. In practice, it functions as a non-identifying key that ties together records such as survey answers, administrative data, and demographic information while preserving privacy.

Formats and generation: Respondent IDs can be numeric strings, alphanumeric codes, or globally unique identifiers (GUID/UUID). They are typically generated by the data collection platform or by a data manager and stored separately from direct identifiers. In longitudinal research, the same RespondentID is used across waves to track changes over time.

Privacy and governance: Because RespondentIDs are used to link data, they must be protected to prevent re-identification. Depending on policy, they may be hashed, pseudonymized, or replaced with tokens when datasets are prepared for sharing. The ID itself should not reveal sensitive personally identifiable information, and access to the mapping between IDs and real identities should be restricted and auditable. Good data governance includes documentation of how IDs are created, stored, and linked, as well as procedures for de-identification and data retention.