Published by: HL7 Orders and Observations Workgroup

Primary Author: Eric M Haas, Health eData Inc.

A.7.0 Scope and Usage

This Observation Profile is part of the The USLabOrder and USLabReport Implementation Guides. Its scope is US Realm ambulatory care and is based upon existing regulatory requirements for Laboratories and Electronic Health Record Systems (EHR-S) for ordering clinical laboratory results. The content has been modeled after the joint HL7 and The Standards and Interoperability (S and I) Framework Laboratory Orders and Results Interface Initiatives and the HL7 Lab Order Conceptual Specification and V3 Lab Normative Standard. However, much of the content is likely to be usable outside the ambulatory space and in other jurisdictions.

Four Observation profiles are defined to cover the various kinds of result values that are generated by laboratories and Ask at Order entry ('AOE') questions. These profiles are:

• USLabObsQuantity for quantitative or numeric results with required units and reference ranges. For example, this profile would be used to record a Blood Glucose level measurement of 80 mg/dL.
• USLabObsRange for quantitative results that are expressed as ranges with required reference ranges. For example, this profile would be used to record white blood cells (WBCs)in a urine analysis with a value range of 10-20 WBC/HPF.
• USLabObsRatio for titers with required reference ranges. For example, this profile would be used to record an adenovirus total antibody of <1:8
• USLabObsCoded for coded results. For example, this profile would be used to record a Chlamydia trachomatis RNA PCR result of "Not Detected"
• USLabObsOther for the remaining result value datatypes
  • Attachment
  • dateTime
  • Period
  • SampleData
  • string
  • time
  For example, this profile would be used to record a free text entry of a cytology observation, or to record the date of last menstrual period for an ask at order entry question for a pap smear report.
• USLabObsPanel for a panel/battery. This observation lists the set component observations from a panel or battery in the Observation.related element and does not have its own Observation.value. For example a Chlamydia trachomatis + Neisseria gonorrhoeae RNA PCR (GC/CT) panel would have two references to related observations for the Chlamydia trachomatis RNA PCR result and the Neisseria gonorrhoeae RNA PCR result.

These profile are referenced in the USLab DiagnosticReport profile for one or more lab test results. They are also referenced for ask at order ("AOE") questions, other clinically relevant questions and for reporting prior results when requesting a test order using the USLabOrder DiagnosticOrder. Although not specified in this implementation, it may be used in other resources as well.

For the purposes of this profile, all elements listed in the differential profile view are Supported which means that the Laboratory Order/Results Sender SHALL be capable of supplying these elements and or extensions to the Laboratory Order/Results Receiver if the data is available. For the Laboratory Order/Results Receiver Supported means they SHALL consuming the supplied the elements and or extensions sent by the Laboratory Order/Results Sender.

In addition, for the Observation.code element, Supported means that the Laboratory Order/Results Sender SHALL be capable of supplying both the LOINC and the local code if both exist and the Laboratory Order/Results Receiver SHALL be capable of consuming both if they exist. For the Observation.valueCodeableConcept, Supported means that the Laboratory Order/Results Sender SHALL be capable of supplying both the SNOMED CT and the local code if both exist and the Laboratory Order/Results Receiver SHALL be capable of consuming both if they exist.

Both the Laboratory Receiver and Laboratory Sender MAY use the information to control their display of the information.