SIU^S15 — Notification of Appointment Cancellation

The message that notifies an appointment cancellation. Releases booked resources (room, equipment, provider slot), updates the patient portal, and may trigger a replacement proposal.

Purpose

S15 marks the end of life of an appointment that did not occur. It is distinct from S26 (No-Show), which describes a patient who did not attend without cancelling. The cancellation reason is carried in SCH-13 Appointment Reason or in NTE.

Typical cases: patient calls to cancel, unexpected hospitalisation preventing the visit, provider unavailability without replacement, exceptional facility closure.

Segment structure

SIU_S15
  MSH                    Message Header
  SCH                    Scheduling Activity Information
  [ { NTE } ]            Notes
  [ { PID                Patient Identification (1..*)
    [ PD1 ]
    [ { PV1 } ]
    [ { PV2 } ]
    [ { OBX } ]
    [ { DG1 } ]
  } ]
  { RGS                  Resource Group Segment (1..*)
    { AIS | AIG | AIL | AIP }
    [ { NTE } ]
  }

Real-world example

Patient cancels their 20/05 consultation for travel reasons:

MSH|^~\&|SCHED|HOSP01|EHR|HOSP01|20260516150000||SIU^S15^SIU_S15|MSG-SIU-S15-001|P|2.5.1|||AL|NE
SCH|APP2026-042||APPT2026-042||1^Routine||CONS^Consultation||30|min|^^^20260520093000^20260520100000|||PATIENT^Patient request^L||||DRJONES^Jones^Sarah^^^DR.|+33142000000^^WORK||||DRJONES^Jones^Sarah^^^DR.|||||Cancelled
PID|1||MRN567890^^^HOSP^MR||DOE^JOHN^A^^MR.||19720515|M
PV1|1|O|CARDIO^^^HOSP01|||||DRJONES^Jones^Sarah^^^DR.
RGS|1|A
AIS|1|A|99213^Office visit, level 3^CPT||20260520093000|||||1800
AIL|1|A|CARDIO-101^^Cardiology Room 101^Cardiology Floor^^HOSP01
AIP|1|A|DRJONES^Jones^Sarah^^^DR.|RP^Responsible Provider^HL70443|20260520093000
NTE|1||Patient cancelled due to travel. No reschedule requested.

• SCH-13 = PATIENT^Patient request^L (reason).
• SCH-25 = Cancelled.
• NTE = free-text detail.
• All resources (AIS, AIL, AIP) remain referenced to allow their release.

Acknowledgment (ACK)

MSH|^~\&|EHR|HOSP01|SCHED|HOSP01|20260516150001||ACK^S15^ACK|ACK-SIU-S15-001|P|2.5.1
MSA|AA|MSG-SIU-S15-001

Common errors

• No cancellation reason: SCH-13 must always be populated. Without a reason, cancellation patterns cannot be analysed.
• S15 / S26 confusion (No-Show): S15 = explicit cancellation; S26 = unannounced absence. Difference matters legally and financially.
• Resources not released: the EHR must process S15 by freeing the room, slot, and equipment. Otherwise double-booking.
• SCH-25 incorrect: Cancelled only (not Modified).
• Late cancellation not flagged: for billing (D-1, D-0 cancellation), enrich with a structured OBX or NTE.

Related messages

See also: SIU^S12, SIU^S13, FHIR Appointment.