HL7 QRY_PC4 (Patient Care Problem Query) | Integration Soup HL7 Reference Guide

HL7 QRY_PC4 Patient Care Problem Query

An older patient-care query for asking about a patient's problem list.

HL7 message structure QRY_PC4 groups and segments from HL7 v2.5.1 Hide structure

These are the generated groups and segments for the version selected at the top of the page. The article explains the workflow, and this panel follows the chosen HL7 version.

Message Structure

Segment	Name	Required	Repeatable
MSH	Message Header	Yes	No
SFT	Software Segment	No	Yes
QRD	Original-Style Query Definition	Yes	No
QRF	Original style query filter	No	No

QRY_PC4 is a patient-care query message for problem information. It uses the original-mode QRD and optional QRF shape, but the business question is clinical: "tell me about this patient's problems."

You are most likely to see QRY_PC4 in older patient-care interfaces, legacy clinical repositories, or migration bridges. Modern systems often expose problem lists through other HL7 profiles, FHIR APIs, or direct database services, but QRY_PC4 still appears where old v2 patient-care workflows remain in production.

A small QRY PC4 example

MSH|^~\&|CAREAPP|CITYHOSP|CLINREPO|CITYHOSP|20260717112500||QRY^PC4^QRY_PC4|QRYPC40001|P|2.5.1 QRD|20260717112500|R|I|QRYPC40001|||20^RD|123456^^^CITYHOSP^MR|PROBLEM|CITYHOSP QRF|CLINREPO|20240101000000|20260717235959|ACTIVE

What workflow it represents

A requester asks the patient-care source for problem details for a patient or account. The response side is profile-dependent, but the data being requested usually corresponds to problem detail content such as PRB records.

Because problem lists affect clinical decision support, intake workflows, and care plans, the receiver should be clear about whether it returns active problems only, historical problems, provisional problems, or problems from a particular visit or source.

How to read the structure

MSH identifies QRY^PC4^QRY_PC4. QRD is required and carries the query timing, priority, ID, subject, quantity limit, and topic. QRF is optional and is commonly used to narrow the source, date range, or status.

The structure is small because the details live in the query profile and response agreement. The segment list tells you how to send the question, not the exact clinical semantics of every filter.

Implementation traps

The dangerous trap is ambiguity around "problem." One system may return diagnoses, another may return an active problem list, and another may mix local problem records with billing diagnoses. Write down exactly what the receiver considers in scope.

Also watch status and date filters. A problem marked inactive, resolved, entered in error, or superseded may still matter for history but should not quietly appear as an active condition.

Reference notes

HL7 terminology identifies PC4 as the patient-care problem query trigger, and message-library references list QRY_PC4 as the problem query structure. Later terminology marks several older patient-care query events as deprecated, so treat this as a legacy interoperability page.