Patient+Discovery+Home

=Patient Discovery= For questions, feedback, and open issues being addressed for this specification, visit the Implementer Questions and Feedback Page

Please visit the Nationwide Health Information Network Inventory page on the ONC website in order to access the latest version of this specification

Specification Definition
Defines the mechanism by which one Nationwide Health Information Network Node can query another to determine if it is a source of information for a specific patient. This query is intended to be directed to the most likely source nodes, as opposed to broadcast across the Nationwide Health Information Network. Patient Discovery follows the following pattern:


 * 1) The initiating Nationwide Health Information Network Node sends a patient discovery request to one or more patient discovery web service end points for target (responding) Nationwide Health Information Network Nodes obtained from the Nationwide Health Information Network Web Services Registry. The request includes a set of demographic attributes associated with the patient for whom the requestor is seeking sources of information.


 * 1) Each responding Nationwide Health Information Network Node attempts to match the set of demographics provided by the requestor with those in its own master person index (MPI). If a single match (one per assigning authority) is achieved, the responding node responds with the Patient Identifier (PID) and the set of demographics locally associated with the matched person. If a single match cannot be achieved, the target may respond with an error condition which may either request additional attributes or indicate a match cannot be achieved.


 * 1) The initiating Nationwide Health Information Network Node may either accept the candidate match or evaluate the returned set of demographics to determine if agrees with the match.

A successful match allows the initiating Nationwide Health Information Network Node to retrieve the PID used to identify the patient by the responding node. That PID is used for subsequent patient-specific transactions with the responding Nationwide Health Information Network Node.

===Transaction Standard===

 Nationwide Health Information Network Patient Discovery utilizes IHE ITI-55: Cross Gateway Patient Discovery (XCPD) transaction. XCPD has not yet been evaluated by HITSP. XCPD has been constrained within this Nationwide Health Information Network specification to exclude one of the described transaction modes.