Glossary · Standards

PIX and PDQ

Patient Identifier Cross-referencing and Patient Demographics Query

Updated

PIX and PDQ are the IHE profiles for patient identity: PIX cross-references a patient's identifiers across systems, and PDQ lets a system search for a patient by demographics.

Together they are how an MPI is queried in an IHE-based exchange; FHIR versions (PIXm, PDQm) exist for REST clients.

Official source

IHE ITI Technical Framework, PIX

See also

MPIPatient matchingIHEXDSPatient

Explained in depth

Digital health

Patient matching and the master patient index: how systems know two records are the same person

When data from several clinics comes together, systems must decide which records belong to the same person. How deterministic and probabilistic matching work, what a master patient index (MPI) does, the FHIR Patient $match operation, and why patient-held records avoid part of the problem.

26 October 2026

Definitions written by Anpheros from the official sources linked on each page. General information about standards and regulation, not legal or medical advice. All terms →

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