Where does blinding collide?

In cryptography, blinding is multiplying a message by a secret random factor so that it can be processed, most often signed, without the processor learning its true content, after which the requester removes the factor to recover a valid signature on the original. Chaum's 1983 Blind signatures for untraceable payments introduced the technique as the basis for digital cash in which a bank signs a coin it cannot see and therefore cannot later link to the spender. The referent is a protocol step that hides an input behind a random mask, distinct from a clinical trial's concealment of treatment assignment, which shares only the metaphor of a party being kept unable to see.[1]

Unit

Whether a value can be processed while its content stays hidden from the processor

Recovery means

Not applicable

Measured by

Established by proofs of blindness (the signer cannot link a signature to its signing session) alongside unforgeability

In clinical research, blinding is keeping participants, caregivers, outcome assessors, or analysts unaware of which treatment each person received, so their expectations cannot distort how they report symptoms, deliver care, or judge results. Schulz and Grimes' 2002 Blinding in randomised trials: hiding who got what distinguishes the parties who can be blinded and warns that the loose label "double-blind" obscures exactly who was kept unaware. The referent is a bias-control procedure in study design, measured by whether allocation stayed concealed, and it is unrelated to a cryptographic blinding factor beyond the shared idea of deliberately withheld knowledge.[2]

Unit

Which parties in a trial are kept unaware of treatment allocation

Recovery means

Not applicable

Measured by

Judged by documented concealment procedures and tests of whether participants or assessors could guess allocation