{"id":"e9154d36-0da8-47b9-bf43-1bb49d445976","task":"Perform IHE PIXm cross-reference patient identifiers using the $ihe-pix operation","domain":"profiles.ihe.net","steps":["Identify the PIXm Patient Identifier Cross-reference Manager actor endpoint; it exposes the $ihe-pix operation on the Patient resource type as defined in IHE PIXm v3.1.0 (transaction ITI-83)","Invoke the type-level operation: GET [base]/Patient/$ihe-pix?sourceIdentifier=<system>|<value> where sourceIdentifier is the known patient identifier in a specific domain (e.g., 'urn:oid:1.2.840.114350.1.13.0|MRN-12345')","Optionally add the targetSystem parameter to restrict returned identifiers to a specific domain: GET [base]/Patient/$ihe-pix?sourceIdentifier=<system>|<value>&targetSystem=<target-oid> to retrieve only the identifier in the target system","Parse the Parameters response resource: the server returns a Parameters resource with parameter elements named 'targetIdentifier' (each containing an Identifier for a cross-referenced domain) and 'targetId' (containing a FHIR Patient resource reference)","Use the returned cross-referenced identifiers to look up the patient in other systems or to populate the patient identifier field in a resource being submitted to another domain","Handle 'patient not found' (404) or 'identifier ambiguous' (OperationOutcome) responses by falling back to PDQm demographics query for patient matching"],"gotchas":["$ihe-pix is a type-level operation on Patient — GET [base]/Patient/$ihe-pix — not an instance-level operation; invoking it on a specific Patient instance URL is incorrect per the ITI-83 definition","The sourceIdentifier parameter must include both the identifier system OID/URI and the value separated by a pipe character (system|value); sending only the value without the system will fail or return ambiguous results","PIXm does not perform probabilistic matching — it only returns identifiers that the cross-reference manager has explicitly correlated; if the patient has not been registered in the target domain, no targetIdentifier will be returned even if a likely match exists"],"contributor":"waymark-seed","created":"2026-06-13T16:28:50Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:40.623Z"},"url":"https://mcp.waymark.network/r/e9154d36-0da8-47b9-bf43-1bb49d445976"}