LRI Pilots High Priority Items
Introduction
This paper summarizes the requirements for the following LRI Pilot High Priority Focus Items.




LOINC
SNOMED
OIDS
UCUM
The requirements were gathered from the



LRI Strategy and Consensus Statement: http://wiki.siframework.org/LRI+Strategy+and+Consensus+Statement
HL7 Version 2.5.1 Implementation Guide Laboratory Results Interface for US Realm Draft 0.6 LRI IG ( v 0.6 submitted to HL7)
LRI In Scope Lab Tests List of In-Scope Lab Tests
1. LOINC
a. From the LRI Strategy and Consensus Statement
The use of LOINC as the standard
vocabulary for communicating
LOINC (Laboratory
In-Scope Tests)
the performed test to obtain results
Consensus has been reached on requiring the use of the LOINC vocabulary but not
constraining labs to using specific LOINC terms. Requires that the LOINC terms
transmitted are valid.
b. From the Balloted Version of the HL7 Version 2.5.1 Implementation Guide: Laboratory Results Interface for US Realm,
S
E
Q
Element
3
Observation
Identifier
DT
CWE
Last Updated 10/31/2011
Use
TABLE 3-11. OBSERVATION RESULT SEGMENT (OBX)
Cardinality
LEN
C.LEN
Value Set
R
[1..1]
Laboratory Observation
Identifier Value Set
Description/Comments
Unique identifier for the type of observation. This field provides
a code for the type of observation. OBX-3 in conjunction with
OBX-4 Observation Sub-ID should uniquely identify this OBX
from all other OBXs associated with this OBR.
LOINC is used as the coding system for this field. Local codes
1
LRI Pilots High Priority Items
may also be used in conjunction with LOINC codes
When populating this field with values, this guide does not give
preference to the triplet in which the standard (LOINC) code
should appear.
.3.12.1 OBSERVATION IDENTIFIERS, OBSERVATION VALUES, INTERPRETATIONS AND COMMENTS
Laboratory results fall into several broad categories or types of results. The first type of result is a quantitative measure of some
property of a specimen and is typically numerical in nature. Often these numeric results are also associated with some sort of
interpretation, typically in terms of the normality or abnormality of the measured quantity in relationship to a reference range or
normal range. Another type of result is a qualitative result related to the testing of a specimen. This is typically coded or textual in
nature. Qualitative results may actually be interpretations of more detailed quantitative measurement. Finally, both quantitative and
qualitative results may have comments associated with them. These comments may provide additional clarification, information
regarding how the result was obtained, etc.
How a particular result should be reported using the OBX segment above depends upon what is being used as an observation
identifier for OBX-3. This guide assumes that LOINC is normally being used for the identification of observations. LOINC identifiers
can easily be classified as quantitative or qualitative. The LOINC scale property QN (quantitative) indicates that the LOINC identifier
is quantitative. All other LOINC identifiers can be treated as qualitative for the purpose of this discussion. Those OBX’s associated
with quantitative LOINC identifiers should be using OBX-5 with either the NM (numeric), SN (structured numeric), TS (timestamp),
DT (date) or TM (time) data types. These quantitative results can be accompanied by an interpretation. Coded interpretations should
be reported using OBX-8 (abnormal flags) when the values have been drawn from HL7 table 0078. When a coded interpretation is
sent, or when a textual interpretation is sent, a second OBX using a non-quantitative LOINC identifier should be used.
c. From The Vocabulary Workgroup In-Scope Test List
Example Entries
Target
Propose
d
category
Test componen
t / scale /
time
Methods
ACLA
Creatinin
e Panel
Chemistr
y
Collection
duration of
urine
methodles
s
Last Updated 10/31/2011
Test
Descriptio
n
Specimen
Exampl
e
LOINC
Codes
SHORTNAM
E
Urine
13362-9
Collect
duration Time
Ur
LONG
COMMON
NAME
Sample
Values/unit
s
Status
Targete
d
Format
(A1, A2,
A3, A4,
B1, B2,
B3, B4)
Collection
duration of
Urine
2
LRI Pilots High Priority Items
in 24
hour
Urine
ACLA
Creatinin
e Panel
in 24
hour
Urine

Chemistr
y
Creatinine
methodles
s
Urine
2161-8
Creat UrmCnc
Creatinine
[Mass/volume
] in Urine
mg/dL
Added
to flesh
out top
three
hundre
d
d. Questions
What are the problems with using the Example LOINC Codes from the In Scope Test List or your own lab’s LOINC code in OBX3?
2. SNOMED
a. From the LRI Strategy and Consensus Statement
SNOMED
The use of SNOMED as a controlled
vocabulary
SNOMED is considered to be a viable vocabulary option for CWE data types but needs to be
confirmed by pilot testing.
b. From the Balloted Version of the HL7 Version 2.5.1 Implementation Guide: Laboratory Results Interface for US Realm,
4.4 SNOMED CT
SNOMED CT is a required vocabulary for communicating coded results when reported as Coded With Exception (CWE) data types in OBX.5 for
specific result categories as defined below.
It is also recommended for specimen source terms in SPM.4.
4.6 VOCABULARY CONSTRAINTS
Laboratory Coded Observation Value Set
For specific result categories:
Organisms
Last Updated 10/31/2011
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LRI Pilots High Priority Items

Identify using codes from the SNOMED CT “organism” hierarchy
o This will normally exclude the use of codes from the “clinical finding” hierarchy representing the presence of a specific organism
(e.g., "312210001^methicillin resistant staphylococcus aureus positive^SCT”, "431256002^culture positive for vancomycin
resistant enterococcus^SCT”, "441070005^Human enterovirus present^SCT”). However, in some cases a specific absence finding
may be appropriate (e.g., "404520004^no Chlamydia trachomatis found^SCT”).
Organism-related substances (e.g. toxin, DNA, RNA, antigen, antibody, etc.)

Identify using codes from the SNOMED CT “substance” hierarchy (e.g., "12671002^Clostridium difficile toxin^SCT”,
"121181000^Chlamydia trachomatis DNA^SCT”, "121006005^influenza virus A antigen^SCT”)
o This will normally exclude the use of codes from the “clinical finding” hierarchy representing the presence of a specific organismrelated substance (e.g., "310541005^Clostridium difficile toxin A detected^SCT”). Currently (as of the January 2011 release) we
are not aware of any SNOMED CT codes representing the absence of an organism-related substance.
Presence and absence findings

Identify using codes from the SNOMED CT “qualifier value" hierarchy (e.g., "52101004^present^SCT”, "10828004^positive^SCT”,
"2667000^absent^SCT”, "260385009^negative^SCT”)
Anatomic Pathology

Use of SNOMED CT codes is recommended, but further evaluation is needed to determine which hierarchies are appropriate for use
o The NAACCR examples list "abnormal morphology" codes
Clinical genomics and additional clinical areas

Consider whether other vocabularies in addition to, or in place of, SNOMED CT might apply
TABLE 3-12. OBSERVATION IDENTIFIERS
Testing Situation Discussion
Conveys ordinal value and interpretation
Last Updated 10/31/2011
OBX.2
Observatio
n Type
OBX.3
Observatio
n Identifier
: LOINC
part = scale
OBX.5
Observatio
n value
OBX.6 Units
CWE
ORD
Ordinal as a
code.
SNOMED CT
shall be used
when code
exists;
otherwise a
local code.
Sending
[empty]
OBX.8
Abnormal
Flags
May be
populated
with codes
from HL7
table 0078
OBX.7
Reference
Range
May be
populated
NTE Segment
May be populated
with comments, not
clinical findings
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LRI Pilots High Priority Items
ordinals as
codes is the
preferred
ELR
approach.
Conveys observation and interpretation
CWE
NOM
Coded
observation.
SNOMED CT
shall be used
when code
exists;
otherwise it’s
a local code.
[empty]
May be
populated
with codes
from HL7
table 0078
May be
populated
May be populated
with comments, not
clinical findings.
c. Questions
What are the problems including SNOMED Codes in OBX.5 for OBX.2 CWE Values?
3. OIDS
a. From the LRI Strategy and Consensus Statement
OIDs
The usage of OIDs by clinical laboratories, and a discussion of the policy The LRI workgroups will develop a 12-24 month roadmap that
and technology issues surrounding the usage of OID's
focuses on OID piloting and future implementation
b. From the Balloted Version of the HL7 Version 2.5.1 Implementation Guide: Laboratory Results Interface for US Realm,
.5.6 Conformance to this Guide
Conformance to this guide is through the use of a combination of OIDs in MSH-21 as noted below:
Base Profile LRI R1 – ID: 2.16.840.1.113883.9.16
Indicates that the message adheres to the rules set out in this guide. When this profile is present in MSH.21, it shall be accompanied by one of
Profile GU or Profile NG and one of Profile RU or Profile RN. Additionally, other profiles may be present that further constrain the message as
agreed to by two or more exchange parties. However, those profiles are strictly voluntary and shall not conflict with any of the three profiles
already listed, nor shall any additional profile be marked by any exchange party as minimally required to successfully send or receive Lab Results
when Profile LRI is present in MSH.21.
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LRI Pilots High Priority Items
Profile GU – ID: 2.16.840.1.113883.9.12
Indicates Globally Unique Identifiers are supported via required use of an ISO OID as noted in this guide.
Profile NG – ID: 2.16.840.1.113883.9.13
Indicates Non-Global Identifiers (Profile NG) were constructed using an alternate method for providing strong identifiers noted in this guide; these
identifiers are not guaranteed to be globally unique.
Profile RU –ID: 2.16.840.1.113883.9.14
Indicates that the test can be identified by only using either the placer order number, and/or filler order number.
Profile RN – ID: 2.16.840.1.113883.9.15
Indicates that the test can be identified by using the universal service identifier and either the placer order number or the filler order number.
The Profiles GU and NG are mutually exclusive, as are RU and RN; allowable combinations:
Base + GU + RU
Base + GU + RN
Base + NG + RU
Base + NG + RN
Profiles GU and RN require the Use of OIDS. What do these require?
GU requires OIDS for Assigning Authorities and Facilities in
PID.3 – Patient Identifier List
PID.18 – Patient Account Number
PID.21 – Mother’s Identifier
NK1.12 - Next of Kin / Associated Parties Employee Number
NK1.33 - Next of Kin/Associated Party’s Identifiers
PV1.5 – Preadmit Number
PV1.19 – Visit Number
PV1.50 – Alternate Visit ID
MSH.21 – Message Profile Identifier
Last Updated 10/31/2011
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LRI Pilots High Priority Items
ORC.2 – Placer Order Number
ORC.3 – Filler Order Number
ORC.4 – Placer Group Number
OBR.2 – Placer Order Number
OBR.3 – Filler Order Number
OBX.18 – Equipment Instance Identifier
ORC.8 – Parent
OBR.29 – Parent
SPM.2 – Specimen Identifier
SPM.3 – Specimen Parent IDs
MSH.3 – Sending Application
MSH.4 – Sending Facility
MSH.5 – Receiving Application
MSH.6 – Receiving Facility
MSH.34 – Last Update Facility
FSH.3 – File Sending Application
FSH.4 – File Sending Facility
FSH.5 – File Receiving Application
FSH.6 – File Receiving Facility
BHS.3 – Batch Sending Application
BHS.4 – Batch Sending Facility
BHS.5 – Batch Receiving Application
BHS.6 – Batch Receiving Facility
PV1.7 – Attending Doctor
PV1.8 – Referring Doctor
PV1.9 – Consulting Doctor
PV1.17 – Admitting Doctor
PV1.52 – Other Healthcare Provider
PV2.13 – Referral Source Code
ORC.10 – Entered By
ORC.11 – Verified By
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LRI Pilots High Priority Items
ORC.12 – Ordering Provider
ORC.19 – Action By
OBR.10 – Collector Identifier
OBR.16 – Ordering Provider
OBR.28 – Result Copies To
OBX.16 – Responsible Observer
OBX.25 – Performing Organization Medical Director
SFT.1 – Software Vendor Organization
NK1.13 – Organization Name
PV2.23 – Clinic Organization Name
ORC.21 - Ordering Facility Name
OBR.23 – Performing Organization Name
RN requires OIDs for
ORC.2 – Order Place Number or OBR.2 Placer Order Number} + OBR.4 – Universal Service Identifier
ORC.3 – Filler Order Number or OBR.3 – Filler Order Number} + OBR.4 – Universal Service Identifier
OBR.29 – Parent + OBR.50 – Parent Universal Service Identifier
ORC.8 – Parent or OBR.29 – Parent} + OBR.50 – Parent Universal Service Identifier
c. Questions
What are the problems with using implementing Profile GU?
What are the problems with implementing Profile RN?
4. UCUM
a. From the LRI Strategy and Consensus Statement
UCUM
Suitability of UCUM as the standard for units of measure to be used as The LRI workgroups will develop a 12-24 month roadmap that
part of a laboratory reporting implementation guide
focuses on UCUM piloting and future implementation
b. From the Balloted Version of the HL7 Version 2.5.1 Implementation Guide: Laboratory Results Interface for US Realm,
Last Updated 10/31/2011
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LRI Pilots High Priority Items
Identifies UCUM Units of Measure to be used in
TQ1.2 Quantity; TQ1.5 Relative Time and Units; TQ1.6 Service Duration; TQ1.13 Occurrence Duration. All fields that have the TQ1 data type are
deprecated.
OBX.6 Units - Usage C(R/RE) with a CWE data type and Cardinality 0..1.. Units of Measure are only required for 2 data types.
The following table gives examples of how the different fields in the OBX segment interact to create the complete observation
TABLE 3-12. OBSERVATION IDENTIFIERS
Testing Situation Discussion
OBX.2
OBX.3
OBX.5
OBX.6 Units OBX.8
OBX.7
NTE
Observation Observation Observation
Abnormal
Reference
Segment
Type
Identifier:
value
Flags
Range
LOINC part
= scale
Numeric result along with
NM
QN
number
May be
May be
May be
May be
interpretation
populated
populated
populated
populated
with UCUM
with codes
with
Units
from HL7
comments,
table 0078
not clinical
findings.
Numerical intervals, ratios,
inequalities
SN
QN
structured
numeric
May be
populated
with UCUM
Units
May be
populated
with codes
from HL7
table 0078
May be
populated
May be
populated
with
comments,
not clinical
findings.
Time like quantitative result with
interpretation
TS, TM, DT
QN
timestamp,
time or date
[empty]
May be
populated
with codes
from HL7
table 0078
May be
populated
May be
populated
with
comments,
not clinical
findings.
c. Questions
1. What are the problems with using UCUM Units of Measure in OBX6 for OBX2 NM and SN values?
Last Updated 10/31/2011
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