HL7 APR Appointment Preferences
HL7 field reference APR fields from HL7 v2.5.1 Show fields
These are the generated fields for the version selected at the top of the page. The document stays the same, but the reference panel follows that version.
Fields
APR is the HL7 Appointment Preferences segment. The APR segment contains parameters and preference specifications used for requesting appointments in the SRM message. It allows placer applications to provide coded parameters and preference indicators to the filler application, to help determine when a requested appointment should be scheduled. An APR segment can be provided in conjunction with either the ARQ segment or any of the service and resource segments (AIG, AIS, AIP, and AIL). If an APR segment appears in conjunction with an ARQ segment, its parameters and preference indicators pertain to the schedule request as a whole. If the APR segment appears with any of the service and resource segments, then its parameters and preferences apply only to the immediately preceding service or resource.
Scheduling segments carry the appointment story in pieces: request, service, resource group, location, personnel, preferences, and timing.
The v2.5.1 structures show APR in SQM_S25 (Schedule query message and response), SRM_S01 (Request new appointment booking). That tells you where it can appear, but the local implementation guide still decides which optional fields are meaningful.
Scheduling flows are easier to reason about when the request, resource, and appointment fields are visible together. HL7 Soup Web is helpful for inspection, and Integration Soup can keep resource mapping and routing rules explicit.
So this page stays intentionally practical: what each field is for, what shape the generated v2.5.1 data gives it, and where I would be careful before mapping it.
APR-1 expresses time preferences, not a confirmed appointment time. It is where a placer can say things like preferred days, preferred start windows, earliest/latest times, or other locally agreed time-selection rules.
This field repeats because a real request often has several acceptable options. The filler still owns the schedule, so treat these as constraints or preferences that help find slots, not as proof that a booking already exists.
APR-2 adds preferences about the resource choice. This might narrow equipment, staff pools, resource classes, or other resource properties beyond what appears in AIG, AIL, or AIP.
Keep it consistent with the surrounding resource segments. If AIP asks for a named clinician but APR-2 says "any provider", the filler has to guess which instruction wins.
APR-3 is for location preferences, such as preferred facility, campus, area, room type, or other location criteria the filler understands. It is broader than AIL-3, which can identify the actual scheduled location.
Use this field when a preference genuinely affects slot selection. If the request must use one specific location, that constraint probably belongs in AIL as well, not only in APR.
APR-4 tells the filler how finely to space returned slot options, usually in minutes. For example, a 15-minute spacing asks the filler to offer candidate starts at 09:00, 09:15, 09:30, and so on within the requested range.
This is mostly useful in query and slot-search workflows. It should be a positive value that matches the filler application's slot granularity; otherwise the response may look precise while still being unusable.
APR-5 lets the placer pass criteria that the filler may use to override normal selection behavior, if the implementation allows it. This is intentionally local and profile-driven.
Be cautious with it. Anything called "override" should have a narrow code set, an audit expectation, and clear rules about who is allowed to send it. Otherwise it becomes a quiet way to bypass scheduling policy.
Related links
- SCH - Scheduling Activity Information
- ARQ - Appointment Request
- RGS - Resource Group
- AIS - Appointment Information
- AIG - Appointment Information - General Resource
- AIL - Appointment Information - Location Resource
- AIP - Appointment Information - Personnel Resource
- TQ1 - Timing/Quantity
- SQM_S25 - Schedule query message and response
- SRM_S01 - Request new appointment booking