ServiceRequest — Procedure, lab or imaging order

FHIR's order resource for anything that is not a medication: lab test, imaging procedure, physiotherapy, intervention, nursing care.

Purpose of the resource

ServiceRequest is the generic FHIR request resource for health services. It covers blood panel orders (LOINC 58410-2), brain MRI requests, physiotherapy session bookings, and specialist consults. Medications have their own resource — MedicationRequest — to keep the workflow, dosage, dispensing and administration route distinct.

ServiceRequest sits inside the FHIR Request workflow pattern: an intent to perform, which materialises into a Procedure (or DiagnosticReport for results) once the act is executed. A typical chain: ServiceRequest → Task → Procedure / DiagnosticReport.

Key fields

The StructureDefinition lists 33 top-level elements. The most prominent:

Lifecycle (status & intent)

ServiceRequest inherits the workflow.Request FHIR pattern. The pair status × intent drives the whole state machine:

• intent=proposal + status=draft — proposal under review.
• intent=order + status=active — active order transmitted to performer.
• intent=filler-order — order generated by the performer itself (typical in radiology when a RIS breaks the exam into sub-acts).
• status=on-hold — temporarily suspended.
• status=revoked — cancelled before execution.
• status=completed — executed, awaiting Procedure / DiagnosticReport creation.

JSON example

Order for a complete blood count (CBC, LOINC 58410-2) on Patient "example", by Dr Jones, to be performed by the ACME lab:

{
  "resourceType": "ServiceRequest",
  "id": "lab-cbc",
  "status": "active",
  "intent": "order",
  "category": [{
    "coding": [{
      "system": "http://snomed.info/sct",
      "code": "108252007",
      "display": "Laboratory procedure"
    }]
  }],
  "priority": "routine",
  "code": {
    "coding": [{
      "system": "http://loinc.org",
      "code": "58410-2",
      "display": "Complete blood count (hemogram) panel - Blood by Automated count"
    }]
  },
  "subject": { "reference": "Patient/example" },
  "encounter": { "reference": "Encounter/example" },
  "authoredOn": "2026-05-14T09:15:00+01:00",
  "requester": { "reference": "Practitioner/dr-jones" },
  "performer": [{ "reference": "Organization/lab-acme" }],
  "reasonCode": [{
    "coding": [{
      "system": "http://snomed.info/sct",
      "code": "75102001",
      "display": "Routine general medical examination"
    }]
  }],
  "specimen": [{ "reference": "Specimen/blood-001" }]
}

• status=active + intent=order: the request is enforceable.
• category SNOMED CT 108252007 = "Laboratory procedure".
• code in LOINC 58410-2 = automated CBC on blood.
• specimen points to existing Specimen/blood-001.
• reasonCode SNOMED CT 75102001 = routine medical examination.

REST API

• GET /ServiceRequest?subject=Patient/example&status=active — active requests for a patient.
• GET /ServiceRequest?category=108252007&_lastUpdated=ge2026-05-01 — recent lab requests.
• POST /ServiceRequest — create a new request.
• PUT /ServiceRequest/lab-cbc — update (status change, note added).
• GET /ServiceRequest?_include=ServiceRequest:specimen — include associated Specimen.
• GET /ServiceRequest?_revinclude=DiagnosticReport:based-on — also fetch the diagnostic reports produced.

National profiles

Common pitfalls

• Mixing code and orderDetail — code says what, orderDetail precises specific modalities. Never bury a modality inside code as a free-text label.
• Missing intent — it is mandatory. Without it, the server rejects creation (HTTP 422). Pick between order (sent to filler) and plan (intent not yet transmitted).
• Confusing with MedicationRequest — a drug goes through MedicationRequest, not ServiceRequest. Chemotherapy can be both (the administration session = ServiceRequest, the drug = MedicationRequest, linked by basedOn).
• Status inconsistent with workflow — moving from active back to draft is forbidden. Every transition must respect the state machine (see Request Pattern).
• Local identifier omitted — many EHRs forget to fill identifier with the local placer number, which complicates legacy reconciliation.

Related resources

• MedicationRequest — equivalent for medications.
• DiagnosticReport — result produced by executing the request.
• Procedure — executed act in response to the ServiceRequest.
• Specimen — referenced biological specimen.
• Task — orchestration of execution between placer and filler.
• HL7 v2 ORM^O01 — legacy equivalent.