V 2.8 HL7 Proposal
Change Request ID:
File Name:
Description:
Status:
Sponsoring Person
Sponsoring Business Unit
Date Originated:
HL7_ACLA_V2_ProposalOM1-31_20090728.doc
Change cardinality for OM1-31 Observations
Required to Interpret This Observation (00616).
New Proposal
Ken McCaslin
American Clinical Laboratory Association (ACLA)
7/28/2009
Date HL7 approved:
Backward Compatible:
Yes
Forward Compatible:
Yes
HL7 Status & Date
1 JUSTIFICATION DETAIL:
The field in the OM1 segment position 31 Observations Required to Interpret This
Observation is defined with cardinality of 1. In many cases this is acceptable however, for
laboratories there are situations where there is a need for more than a single analyte
information including something as simple as Creatinine Clearance which requires both a
Urine Volume and the number of hours of the collection (typically 24 hours). There are more
complex testing that requires many Observations to be provided by the Ordering Provider at
the time they collect the specimen. Worse case examples include MSAFP and Pap Smears
as outlined below:
Maternal Serum Alpha Feta Protein:
Require the following:
Maternal Weight
Estimated Date of Delivery
How the Estimated Date of Delivery was calculated
Mother’s Ethic Origin
Number of Fetuses
Insulin-Depend Diabetic (Y/N)
History of Neural Tube Defects (Y/N)
History of Down Syndrome (Y/N)
Each of these items are use to do the calculation of the final result values and with any of
these missing, the final observation cannot be provided. Therefore, this proposal
requests that OM1-31 be a repeating field. Based on current known requirements there
could be a limit of 20 repeats, however, as new tests are developed in the future it is
unknown what the upper limit could need to be set at and therefore this proposal is to
have unlimited repeats.
2 OPEN ISSUES:
NA
3 CHANGE REQUEST IMPACT:
Chapter 10 – Scheduling
Section 8.8.8 – OM1 General Segment
The Segment Chart
Sub Section 8.8.8.31
OM1 -31
4 DOCUMENTATION CHANGES:
30
250
CWE
O
31
250
CWE
O
32
65536
TX
O
33
250
CWE
O
34
250
CWE
O
Y
Y
0177
00615
Confidentiality Code
9999
00616
Observations Required to Interpret the Observation
00617
Interpretation of Observations
9999
00618
Contraindications to Observations
9999
00619
Reflex Tests/Observations
OM1-31 Observations Required to Interpret This Observation (CWE) 00616
Components:
<Identifier (ST)> ^ <Text (ST)> ^ <Name of Coding System (ID)> ^ <Alternate Identifier
(ST)> ^ <Alternate Text (ST)> ^ <Name of Alternate Coding System (ID)> ^ <Coding System
Version ID (ST)> ^ <Alternate Coding System Version ID (ST)> ^ <Original Text (ST)>
Definition: This field contains the list of variables that the diagnostic service needs to interpret the
results of an ordered study. The observations specified here should be sent to the diagnostic
service as OBX segments along with the order (OBR) segment.
Example for cervical pap smear:
...|2000.32^date last menstrual period^AS4~2000.33^menstrual state^AS4|...
Example for arterial blood gas:
...|94700^inspired 02^AS4|...
These examples use AS4 codes in code/text format to identify the variables. Separate multiple
items by repeat delimiters.
It appears there will not be any change other than in the Segment Chart in Section 8.8.8 since the sub
section already describes the process for repeating this field consistent with the process followed for the
Reflex Tests in OM1-34. the only missing item is Cardinality in the segment chart.