A record of a request for a diagnostic investigation service to be performed.

Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller.

The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the notes section below.

Protocol or definition followed by this request.

Plan/proposal/order fulfilled by this request.

The request takes the place of the referenced completed or terminated request(s).

Composite request this is part of.

The status of the order.

Typically the system placing the order sets the status to "requested". Thereafter, the order is maintained by the receiver that updates the status as the request is handled.

Whether the request is a proposal, plan, an original order or a reflex order.

A code that identifies a particular diagnostic investigation, or panel of investigations, that have been requested.

Many laboratory tests and radiology tests embed the specimen/organ system in the test name, for example, serum or serum/plasma glucose, or a chest xray. The specimen may not be recorded separately from the test code.

On whom or what the investigation is to be performed. This is usually a human patient, but diagnostic tests can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans).

An encounter or episode of care that provides additional information about the healthcare context in which this request is made.

The date/time at which the diagnostic testing should occur.

When the request transitioned to being actionable.

Who/what is requesting diagnostics. The practitioner that holds legal responsibility for ordering the investigation.

This not the dispatcher, but rather who is authorizing.

Desired type of performer for doing the diagnostic testing. (.

this is a role, not aparticipation type. I.e. doesn’t describe the task, describes the capacity. Examples “compounding pharmacy” or “psychiatrist” or “internal referral”.

The desired perfomer for doing the diagnostic testing.

Use an extension or listing alternative alternative performers and/or roles and/or preference.

An explanation or justification for why this diagnostic investigation is being requested. This is often for billing purposes. May relate to the resources referred to in supportingInformation.

This may be used to decide how the diagnostic investigation will be performed, or even if it will be performed at all. Use CodeableConcept text element if the data is free (uncoded) text as shown in the CT Scan example.

Additional clinical information about the patient or specimen that may influence test interpretations. This includes observations explicitly requested by the producer(filler) to provide context or supporting information needed to complete the order.

This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". Examples include reporting the amount of inspired oxygen for blood gasses, the point in the menstrual cycle for cervical pap tests, and other conditions that influence test interpretations.

Any other notes and comments made about the service request. (e.g. "patient hates needles").

Key events in the history of the request.

This may not include provenances for all versions of the request – only those deemed “relevant” or important. This SHALL NOT include the Provenance associated with this current version of the resource. (If that provenance is deemed to be a “relevant” change, it will need to be added as part of a later update. Until then, it can be queried directly as the Provenance that points to this version using _revinclude All Provenances should have some historical version of this Request as their subject.