DSC-2 (Continuation Style) shall always contain “I”, signifying that this is part of an interactive continuation message.

3.22.4.1.3 Expected Actions

3.22.4.1.3.1 Immediate Acknowledgement

The Patient Demographics Supplier shall immediately return an RSP^ZV2 response message as specified below in Section 3.22.4.2, “Patient Demographics Response.” The RSP^ZV2 response message incorporates original mode application acknowledgment as specified in the “Acknowledgment Modes” section (ITI TF-2: C.2.3). The Supplier shall use Field MSH-3-Sending Application of the RSP^ZV2 message to return the value it received from the Patient Demographics Consumer in Field MSH-5-Receiving Application of the QBP^ZV1 message.

3.22.4.1.3.2 Query Parameter Processing

The Patient Demographics Supplier shall be capable of accepting, searching on, and responding with attributes in the QPD segment as specified in Table 3.22-2.

The Patient Demographics Supplier must be capable of receiving all valid combinations of subcomponents that make up the Assigning Authority component (i.e., all valid combinations of QPD-3.8).

Handling of phonetic issues, alternate spellings, upper and lower case, wildcards, accented characters, etc., if deemed appropriate, is to be supported by the Patient Demographics Supplier rather than by the Patient Demographics Consumer. The Supplier shall return at least all exact matches to the query parameters sent by the Consumer; IHE does not further specify matching requirements.

3.22.4.1.3.3 Incremental Response Processing

The Patient Demographics Supplier shall be capable of accepting and processing attributes in the RCP segment as listed in Table 3.22-5. In particular, the Patient Demographics Supplier shall respond in immediate mode (as specified by a RCP-1-Query Priority value of I ).

Also, the Patient Demographics Supplier shall be able to interpret RCP-2-Quantity Limited Request to return successive responses of partial lists of records according to the HL7 Continuation Protocol, as described in Section 3.22.4.2 below and in the HL7 Standard.

3.22.4.2 Patient Demographics and Visit Response

3.22.4.2.1 Trigger Events

The Patient Demographics Supplier’s response to the Find Candidates with Visit Information message shall be the following message:

ZV2 – Find Candidates with Visit Information response

3.22.4.2.2 Message Semantics

The Patient Demographics and Visit Response transaction is conducted by the RSP^ZV2 message. The Patient Demographics Supplier shall generate this message in direct response to the QBP^ZV1 message previously received. This message satisfies the Application Level, Original Mode Acknowledgement for the HL7 QBP^ZV1 message.

The segments of the message listed without enclosing square brackets in Table 3.22-6 are required. Detailed descriptions of all segments listed in the table below are provided in the following subsections. Other segments of the message are optional.

Table 3.22-6: RSP Segment Pattern Response

3.22.4.2.2.1 MSH Segment

The MSH segment shall be constructed as defined in the “Message Control” section (ITI TF-2: C.2.2).

Field MSH-3-Sending Application specifies the patient information source that processed the query. The Patient Demographics Supplier shall use Field MSH-3-Sending Application of the RSP^ZV2 message to return the value it received from the Patient Demographics Consumer in Field MSH-5-Receiving Application of the QBP^Q22 message.

Field MSH-9-Message Type shall have all three components populated with a value. The first component shall have a value of RSP ; the second component shall have a value of ZV2 . The third component shall have a value of RSP_ZV2 .

3.22.4.2.2.2 MSA Segment

The Patient Demographics Supplier is not required to send any attributes within the MSA segment beyond what is specified in the HL7 standard. See the “Acknowledgment Modes” section (ITI TF-2: C.2.3) for the list of all required and optional fields within the MSA segment.

3.22.4.2.2.3 QAK Segment

The Patient Demographics Supplier shall send attributes within the QAK segment as defined in Table 3.22-7. For the details on filling in QAK-2 (Query Response Status) refer to the “Patient Demographics Supplier Actor Query Response Behavior” Section 3.22.4.2.2.11.

QAK-1 (Query Tag) shall echo the same value of QPD-2 (Query Tag) of the QBP^Q22 message, to allow the Patient Demographics Query Consumer to match the response to the corresponding query request.

Table 3.22-7: IHE Profile - QAK segment

Adapted from the HL7 standard, version 2.5

3.22.4.2.2.4 QPD Segment

The Patient Demographics Supplier shall echo the QPD Segment value that was sent in the QBP^ZV1 message.

3.22.4.2.2.5 PID Segment

The Patient Demographics Supplier shall return one PID segment group (i.e., one PID segment plus any segments associated with it in the message syntax shown in Table 3.22-6) for each matching patient record found. The Supplier shall return the attributes within the PID segment as specified in Table 3.22-8. If the Pediatric Demographics Option is supported, then additionally, the Supplier shall return the attributes within the PID segment as specified in Table 3.22-9. In addition, the Patient Demographics Supplier shall return all other attributes within the PID segment for which it is able to supply values.

Table 3.22-8: IHE Profile - PID segment

Table 3.22-8a: IHE Profile, Pediatric Demographics Option - PID segment

Adapted from the HL7 standard, version 2.5

The Patient Demographics Supplier may or may not be able to supply additional identifiers from the domains specified in QPD-8. Inability to supply an identifier in a particular domain is not an error, provided that the domain is recognized.

The PID segment and the PD1, PV1, PV2, and QRI segments that are associated with it are returned only when the Patient Demographics Supplier is able to associate the search information in QPD-3 with one or more patient records in the patient information source associated with MSH-5-Receiving Application . See the “Patient Demographics Supplier Actor Query Response Behavior” Section 3.22.4.2.2.11) for a detailed description of how the Patient Demographics Supplier responds to the query request under various circumstances.

3.22.4.2.2.6 PD1 Segment

For each patient for which the Patient Demographics Supplier returns a PID segment, it may optionally return the PD1 (Patient Additional Demographics) segment, but is not required to do so.

3.22.4.2.2.7 PV1 Segment

For each patient for which the Patient Demographics Supplier returns a PID segment, it shall also return a PV1 Segment in which attributes are populated as specified in Table 3.22-9. In addition, the Patient Demographics Supplier shall return all other attributes within the PV1 segment for which it is able to supply values.

Table 3.22-9: IHE Profile – PV1 segment

Adapted from the HL7 standard, version 2.5

3.22.4.2.2.8 PV2 Segment

For each patient for which the Patient Demographics Supplier returns a PID segment, it may optionally return the PV2 (Patient Visit – Additional Information) segment, but is not required to do so.

3.22.4.2.2.9 QRI Segment

For each patient for which the Patient Demographics Supplier returns a PID segment, it may optionally return the QRI (Query Response Instance) segment, but is not required to do so. Refer to the HL7 Standard, Version 2.5, Chapter 5, Section 5.5.5, for more information.

3.22.4.2.2.10 DSC Segment

If a number of records is specified in RCP-2-Quantity Limited Request , the Patient Demographics Supplier shall return an incremental response of that number of records when the number of matching records it finds exceeds the number of records specified in RCP-2.

As long as the Patient Demographics Supplier has records to return in additional to those returned in the incremental response, the Supplier shall return a DSC Segment. The single field of the DSC Segment shall contain a unique alphanumeric value (the Continuation Pointer) that the Patient Demographics Consumer may return in the DSC segment of the QBP^ZV1 message to request the next increment of responses. The Supplier shall return increments as many times as the Consumer requests them (and there are increments to return), and shall stop when the Consumer sends a cancel query (QCN^J01) message (or when there are no more increments to return). The Supplier shall signal no more increments by omitting the DSC segment.

3.22.4.2.2.11 Patient Demographics Supplier Actor Query Response Behavior

The Patient Demographics Supplier shall perform the matching of patient data based on the query parameter values it receives. The information provided by the Patient Demographics Supplier to Patient Demographics Consumer Actors is a list of possible matching patients from the patient information source associated with the value that the Consumer sent in MSH-5-Receiving Application of the query message.

If domains are specified in QPD-8-What Domains Returned and are recognized by the Patient Demographics Supplier, the response will also, for each patient, contain any Patient ID values found in the specified domains.

The mechanics of the matching algorithms used are internal to the Patient Demographics Supplier and are outside of the scope of this framework.

The Patient Demographics Supplier shall respond to the query request as described by the following 3 cases:

Case 1 : The Patient Demographics Supplier finds (in the patient information source associated with MSH-5-Receiving Application ) at least one patient record matching the criteria sent in QPD-3-Demographics Fields . No patient identifier domains are requested in QPD-8-What Domains Returned .

AA (application accept) is returned in MSA-1.

OK (data found, no errors) is returned in QAK-2.

One PID-PV1 segment group (i.e., one PID segment and one PV1 segment, plus any segments associated with them in the message syntax shown in Table 3.22-6) is returned from the patient information source for each patient record found. If the Patient Demographics Supplier returns data for multiple patients, it shall return these data in successive occurrences of the PID-PV1 segment group.

Within each PID segment, field PID-3-Patient Identifier List contains one or more identifiers from the set of Patient ID Domains known by the Patient Demographics Supplier.

If an incremental number of records are specified in RCP-2 - Quantity Limited Request , and the number of records found exceeds that incremental number, the Supplier returns only the incremental number of records, followed by a DSC segment containing a uniquely valued Continuation Pointer.

The consumer will specify the value of the continuation pointer in the DSC segment on the subsequent query request to request the next increment of responses.

Case 2 : The Patient Demographics Supplier finds (in the patient information source associated with MSH-5-Receiving Application ) at least one patient record matching the criteria sent in QPD-3-Demographics Fields . One or more patient identifier domains are requested in QPD-8-What Domains Returned ; the Supplier recognizes all the requested domains.

AA (application accept) is returned in MSA-1.

OK (data found, no errors) is returned in QAK-2.

One PID-PV1 segment group (i.e., one PID and one PV1 segment plus any segments associated with them in the message syntax shown in Table 3.22-6) is returned for each matching patient record found. If the Patient Demographics Supplier returns data for multiple patients, it shall return these data in successive occurrences of the PID segment group.

Within each PID segment, field PID-3-Patient Identifier List contains, in successive occurrences delimited by the repetition separator, the identifiers from all the Patient ID Domains requested in QPD-8. In each occurrence of PID-3, component 4 contains the assigning authority value for one Patient ID Domain, and component 1 contains the Patient ID value in that domain. If an identifier does not exist for a domain that was specified on QPD-8, nothing is returned in the list.

If an incremental number of records is specified in RCP-2 - Quantity Limited Request , and the number of records to be sent exceeds that incremental number, the Supplier returns only the incremental number of records, followed by a DSC segment containing a uniquely valued Continuation Pointer.

The consumer will specify the value of the continuation pointer in the DSC segment on the subsequent query request to request the next increment of responses.

Case 3 : The Patient Demographics Supplier does not recognize one or more of the domains in QPD-8-What Domains Returned .

AE (application error) is returned in MSA-1 and in QAK-2.

For each domain that was not recognized, an ERR segment is returned in which the components of ERR-2-Error Location are valued as follows.

ERR-2.4-Field Repetition identifies the ordinal occurrence of QPD-8 that contained the unrecognized domain. As specified by HL7, ERR-2.5-Component Number and ERR-2.6-Subcomponent Number are not valued because we are referring to the entire field QPD-8.

ERR-3-HL7 Error Code is populated with the error condition code 204 (unknown key identifier). Together with the values in ERR-2, this signifies that the Patient Demographics Supplier did not recognize the domain for QPD-8-What Domains Returned .

3.22.4.2.3 Expected Actions

The Patient Demographics Consumer will use the demographic information provided by the Patient Demographics Supplier to perform the functions for which it requested the information, e.g., providing a pick list to the user.

If the Supplier has sent a DSC segment containing a continuation pointer value, additional increments of data are available upon request by the Consumer. After receiving each increment of data that includes a DSC segment containing a continuation pointer value, the Consumer should take one of the following actions.

• If the Consumer wishes to receive another increment of the data, the Consumer reissues the query message using a new unique value in MSH-10-message control ID and adding the DSC segment after the RCP segment. DSC-1 shall echo the continuation pointer returned in RSP^K22 DSC-1 segment.
• If the Consumer does not wish to receive another increment of the data, the Consumer issues a cancel query (QCN^J01) message.
• If the Consumer does not reissue the query or send a cancel query message, the query will eventually terminate.

If the Supplier has not sent a DSC segment containing a continuation pointer value, no more increments of data are available and no further action by the Consumer is required.

3.22.4.3 Canceling a query

The Patient Demographic Consumer can send a cancel trigger to notify the Patient Demographic Supplier that no more incremental response will be requested, and interactive query can be terminated. This cancellation trigger is optional. How long the Patient Demographic Supplier retains query results (for incremental response) is an implementation decision and therefore beyond the scope of IHE.

3.22.4.3.1 Trigger Events

The Patient Demographic Consumer which received a RSP^K22 response message indicating there more incremental response data available, can terminate the interactive query with the following HL7 trigger event:

J01 – Cancel query status

3.22.4.3.2 Message Semantics

Canceling a query is conducted by the QCN^J01 message. The Patient Demographic Consumer can generate this message to notify the Patient Demographic Supplier that no more data is desired. The segments of the message listed below are required, and their details descriptions are provided in the following subsections.

Table 3.22-10: QCN Cancel query

The receiver shall acknowledge this cancel by the HL7 ACK message. See ITI TF-2: C.2.3, “Acknowledgement Modes”, for definition and discussion of the ACK message.

3.22.4.3.2.1 MSH Segment

The MSH segment shall be constructed as defined in the “Message Control” section (ITI TF-2: C.2.2).

MSH-9 (Message Type) shall have three components. The first component shall have the value of QCN; the second component shall have a value of J01. The third component shall have the value of QCN_J01.

3.22.4.3.2.2 QID Segment

The QID segment contains the information necessary to uniquely identify the query being cancelled.

Table 3.22-11: IHE Profile - QID segment

3.22.4.3.2.2.1                         Populating QID-1 Query Tag

QID-1 (Query Tag) uniquely identifies the query to be canceled. This field shall contain the same value specified in QPD-2.

3.22.4.3.2.2.2                         Populating QID-2 Message Query Name

QID-2 (Message Query Name) identifies the name of the query. It is an identifier of the conformance statement for this query. This field shall contain the same value specified in QPD-1.

3.22.5 Security Considerations

3.22.5.1 Audit Record Considerations

The Patient Demographics Query Transaction is a Query Information event as defined in Table 3.20.4.1.1.1-1. The Actors involved shall record audit events according to the following:

3.22.5.1.1 Patient Demographics Consumer audit message:

Where:

3.22.5.1.2 Patient Demographics Source audit message:

Where: