O:
HL7 Structured Documents WG Co-Chairs
CC:
Stanley Huff, MD, HL7 Board Chair
Ken McCaslin, Chair, HL7 TSC
John Quinn, HL7 CTO
FROM:
HL7 Patient Care Allergy and Intolerance Project Team
DATE:
June 30, 2015
RE:
Patient Safety Issue
The purpose of this letter is to bring to the attention of the HL7 Structured Documents Work
Group an issue of concern to the Patient Care WG. This issue relates to the process for changes
related to C-CDA R1.1 and R 2.0, and the timing and limitations placed on these changes
through Project 1014 sponsored by the Structured Documents WG (SDWG) entitled “C-CDA
DSTU 2013 Update”.
Background
The stated project need for SDWG project 1014 is “Proposed US federal regulation has
identified C-CDA 2.0 as being the preferred way forward, but introduces a need for
compatibility that was not anticipated for in the original project scope. An update is needed to
ensure that new templates are backwards compatible.
Existing Consolidated CDA (C-CDA) needs to be enhanced by adding templates to represent
priority data elements, and modified/new section level and document level templates needed for
transitions of care and care plans, areas essential to patient care and the meaningful use of
EHRs; we need to incorporate errata; and we want to address areas that implementers have
found to be ambiguous.” Patient Care is a co-sponsor of this project originally approved in
2013. The TSC approved the updated project scope statement on June 9, 2015.
The Patient Care Work Group (PCWG) has been working on the Allergy and Intolerance topic to
update and harmonize standards since 2010. The products related to this work include an
Allergy and Intolerance Domain Analysis Model, Allergy and Intolerance Clinical Models
(DSTU) and an Allergy and Intolerance FHIR resource. In order to ensure harmonization across
HL7 standards, the Patient Care WG conducted an extensive review of C-CDA R1.1 and R2.0.
During this review, the PCWG presented on-going issues to the SDWG at two face-to-face
sessions (most recently at the Paris WG meeting) in order to reinforce the findings and
recommendations of this year-long analysis of known C-CDA issues. The results of this analysis
were posted as DSTU comments for C-CDA R1.0 (Comment 643) and C-CDA R2.0 (Comment
644). At the request of the SDWG, multiple comments were submitted against each C-CDA
version in tabular format. This summary document can also be found on the Patient Care wiki:
C-CDA Harmonization Table.
The Issue
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Patient Care has kept the SDWG apprised of work in the area of Allergies and Intolerances since
this work began in 2010. Multiple presentations on this topic were given at each Work Group
meeting (see minutes from each joint PCWG/SDWG Thursday Q2). As the PC WG
harmonization process continued, it was apparent that the C-CDA did not recognize some of the
concepts within the PCWG DAM or clinical models, or the FHIR allergy and intolerance
resource. Working with a primary representative and additional representatives from the SDWG,
the PCWG has diligently outlined and proposed solutions to ensure harmonization all of the HL7
products that address allergies and intolerances. This has included extensive terminology work
in coding systems including HL7, SNOMED CT and LOINC.
Extensive comments and recommendations were posted to the DSTU website for both C-CDA
R1.1 and R2.0, with the expectation that these comments would be duly considered during the
current review of errata and backwards compatibility issues. Comments from the PCWG are
substantive and seek to ensure that the use of C-CDA provides clinically correct data exchange
between providers.
On Thursday, June 25, the Patient Care WG presented a synthesis of these comments to the
SDWG. The most significant issue at hand relates to the use of the Severity Template in two
contexts related to the Allergy and Intolerance Observation and the Reaction Observation.
The current relationship of the Severity Template is shown in this diagram taken from C-CDA
R1.1. This relationship is retained in R2.0: The relationship between the allergy observation and
severity is erroneous, is creating confusion through ambiguity and does not reflect the current
relationships in other HL7 allergy and intolerance standards.
The PCWG Allergy and Intolerance DAM and Clinical Models as well as the FHIR resource
have a different relationship.
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Allergy
Intolerance
Observation
Reaction
Criticality
Status
Observation
Severity
A reaction is correctly described by severity, e.g. a patient had a mild reaction to a drug, or a
severe reaction to a food. However, the allergic condition is not described in terms of severity,
rather the term criticality. The concept of criticality is in the RIM as the code “CRIT”1 in
ActCode/ObservationType, and is associated with the allergic or intolerant condition.
The definition of criticality as per the PCWG is as follows: A clinical judgment as to the worst
case result of a future exposure (including substance administration). When the worst case result
is assessed to have a life-threatening or organ system threatening potential, it is considered to be
of high criticality.
It is important to note that there is not a 1:1 relationship between the severity of a reaction and
the criticality of the condition. For example a patient might have a severe reaction to a
medication (nausea) however that condition has a low criticality – e.g. the medication can still be
prescribed if medically indicated. Conversely, a child may have a mild reaction on the first
exposure to a peanut, however a repeat exposure to peanuts may be life threatening and therefore
of high criticality.
After the presentation by the PCWG on June 25 to the SDWG, the group discussed the issues at
hand for some 30 minutes. Despite an acknowledgement of the issues, no resolution was
proposed nor voted on by the SDWG.
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The current RIM definition of criticality is: CRIT (criticality) An observation representing a clinical judgment as
to the worst case result of a future occurrence or the evolution of a current occurrence. It would be based on the
severity of past occurrences, the details of what produced the past occurrences and the life-threatening or organ
system threatening potential of the observation type. The PCWG has a harmonization request pending to update this
definition.
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Patient Safety and Clinical Practice
The PCWG has many other DSTU comments – however, we are writing to ensure that the
criticality concept is included without delay in the C-CDA templates.
Currently the use of severity in the context of a reaction and also in the context of a condition has
the following potential consequences in systems exchanging information on allergies and
intolerances:
1. Patient safety issue: When a system reports an allergic or intolerant reaction with mild
severity but which is associated with a condition of high criticality (e.g. the risk of a life
threatening reaction), based on severity alone a receiving system could allow an order to
be processed for a drug or medication that should not be prescribed. The current
construct in the C-CDA does not capture or convey the correct information to mitigate
this risk.
2. The current construct does not allow for the most effective treatment: A patient may
report a severe reaction to a medication, such as “severe nausea” – however, nausea in
most cases is of low criticality. A similar example is the common reaction to epinephrine
(adrenaline) where most patients would describe their nausea, vomiting and sweating as
severe – but if adrenaline is clinically indicated, it will be prescribed. The current CCDA construct is unable to correctly convey this information.
3. Alert fatigue: Clinicians often complain of alert fatigue, including for alerts for the
severity of an allergic condition, since it is a spurious concept. Given the documented
drug-allergy alert override rate of around 90%2, the use of criticality will clearly convey
issues that require a careful consideration of the clinical options.
In addition to the DSTU comments prepared by the PCWG, the C-CDA R2 ballot comments
included a comment on the use of severity in two contexts. The reconciliation spreadsheet for
the 2013 ballot (Comment 290) noted under the disposition that SDWG would consult with the
Allergy and Intolerance DAM. However the final disposition reads as follows: "In CCD.xml,
add commenting [sic] which relates to the description in the severity template: ""When the
Severity Observation is associated directly with an allergy it characterizes the allergy. When the
Severity Observation is associated with a Reaction Observation it characterizes a Reaction."
This statement is incorrect, and it is unfortunate that the use of criticality (a concept currently
existing in the RIM) was not considered.
The C-CDA R2.1 Project
SDWG is considering candidate errata for C-CDA 2.1, a project designed to ensure backwards
compatibility from R2.0 to R1.1 based on considerations related to the Meaningful Use 3 NPRM.
The project wiki is here:
http://wiki.hl7.org/index.php?title=Consolidated_CDA_R2.1_DSTU_Update and the need for
2
Bryant, AD, Fletcher, GS, Payne, TH. Drug Interaction override rates in the Meaningful Use
era – no evidence of progress. App Clin Infor 2014:5(3);802-813
http://www.ncbi.nlm.nih.gov/pubmed/25298818
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the project opinion is here: http://motorcycleguy.blogspot.com/2015/05/tell-onc-to-use-ccda-21for-stage3-2015.html
What are errata?
The SDWG has discussed what errata are: (the post is the opinion of the author)
http://motorcycleguy.blogspot.com/2013/03/defining-errata.html
The Chicago Manual of Style defines errata as follows: "Errata, lists of errors and their
corrections, may take the form of loose, inserted sheets or bound-in pages. An errata sheet is
definitely not a usual part of a book. It should never be supplied to correct simple typographical
errors (which may be rectified in a later printing) or to insert additions to, or revisions of, the
printed text (which should wait for the next edition of the book). It is a device to be used only
in extreme cases where errors severe enough to cause misunderstanding are detected too
late to correct in the normal way but before the finished (book) is distributed. Then the
errors may be listed with their locations and their corrections on a sheet that is tipped in, either
before or after the book is bound, or laid in loose, usually inside the front cover of the book.
Reference: Chicago Manual of Style: (referenced June 28, 2015)
http://www.chicagomanualofstyle.org/home.html
Is the issue of criticality an erratum? The PCWG feels that the omission of the criticality
concept is of sufficient gravity to qualify as an erratum that must be considered in the current CCDA 2.1 process. The risk of not dealing with the criticality issue at this time is that the
Meaningful Use 3 standard will point to a version of the C-CDA that is clinically incorrect and
has the potential to cause patient harm.
The PCWG understands the alacrity with which the errata process must occur to meet federal
timelines. The current timeline for C-CDA DSTU errata review is due to begin on July 1 and
end on July 10th, 2015. While the HL7 Governance and Operations Manual describes the
process for submission of DSTU errata to the HL7 CTO, the PCWG appeals to the HL7 SDWG
to duly consider this request prior to finalizing C-CDA 2.1 comments through the DSTU errata
process. Normally such an activity would be balloted allowing for broad member comment.
Outcome Requested
The C-CDA is cited as the means to support health information exchange within the NPRM3 for
MU 3. HL7 needs to ensure that the information exchanged is correct, based on current
standards such as the RIM, and responsibly mitigates the risk of ambiguous and clinically
incorrect information. The Patient Care WG respectfully requests that the concept of criticality
be added to the C-CDA standard as an erratum because of the risk of patient harm.
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MU 3 NPRM : https://www.federalregister.gov/articles/2015/03/30/2015-06685/medicare-andmedicaid-programs-electronic-health-record-incentive-program-stage-3
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While the addition of a criticality template to C-CDA would be the most complete solution to
this issue, there are several other paths forward:
1. At a minimum: Change the incorrectly referenced severity template to SHOULD NOT at the
Allergy Intolerance Observation level.
2. If possible: Add a MAY conformance to the Allergy Intolerance Observation that permits use
of the Criticality Observation.
The PCWG stands ready to assist with this endeavor.
Respectfully submitted by the Patient Care WG Allergy and Intolerance Project Team,
Elaine Ayres, Patient Care WG Co-Chair
Stephen Chu, Patient Care WG Co-Chair
Russell Leftwich, Patient Care WG Co-Chair and SME
Lisa Nelson, SDWG liaison to PCWG
Robert Hausam, Patient Care WG terminology and SDWG representative
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