Transcript SNOMED CT-AU: Robyn Richards

Overview, Benefits and how to approach Implementing
- Robyn Richards (NEHTA)
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Australian extension of the international
SNOMED CT
Allows us to add to and ensure the content is
applicable for Australia
Contains all international content plus any Au
additions or changes
Australian Medicines Terminology
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The Basics
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Over 300,000 concepts that are organised into
19 top-level hierarchies
Body structure
Clinical finding
Environment or geographic location
Event
Linkage concept
Observable entity
Organism
Pharmaceutical/biologic product
Physical force
Physical object
Procedure
Qualifier value
Record artefact
Situation with explicit context
Social context
Special concept
Specimen
Staging and scales
Substance
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A concept and its descriptions
SCTID: 22298006
Fully Specified Name
Myocardial infarction (disorder)
Myocardial
infarction
SCTID: 751689013
Preferred term
Myocardial infarction
SCTID: 37436014
Synonym
Synonym
Synonym
Synonym
MI - Myocardial infarction
SCTID: 1784872019
Infarction
of heart
SCTID: 37441018
Cardiac
infarction
SCTID: 37442013
Heart attack
SCTID: 37443015
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Attributes
Over 60 types of attributes
These ‘link’ concepts together to provide definitions
Most important Attribute is the IS-A
The use of IS-A attribute forms the hierarchies
parents-children; types-subtypes; subsumptioninheritance
Other attributes are used to form lateral links
between or across hierarchies
Body Structure has an attribute of Laterality
Procedure has an attribute of Access
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Concepts within the top-level hierarchies exist in a
poly-hierarchical structure
Disorder of lower
Respiratory system
Is A
Is A
Inflammatory disorder
of lower respiratory tract
Disorder of lung
Is A
Is A
Is A
Lung consolidation
Pneumonitis
Is A
Is A
Pneumonia
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Attributes
Causative agent
Virus (organism)
Bronchitis
Pathological process
Infectious process
(morphologic abnormality)
Is A
Viral Bronchitis
Associated
morphology
Finding site
Role grouping
Inflammation
(morphologic abnormality)
Bronchial structure
(body structure)
Pre and Post-coordination
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Pre and post coordination are the names given to
how you approach representing clinical
expressions in a record
Pre coordination encapsulates all the
information to convey meaning in a single
code
Post coordination encapsulates meaning in
a series of attribute value pairs associated
with a concept.
Pre and Post-coordination
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Pre coordinated example
◦ One concept conveys all the required meaning
◦ E.g.
31978002
‘Fracture of tibia’
Post coordinated expression
◦ E.g.
31978002: 272741003 = 7771000
‘Fracture of tibia: laterality = left’
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Group or subset of concepts from SNOMED CT
used for a specific purpose
Implementation tools used to provide a smaller
set of concepts for implementation in a
specific section of a record
There are other uses for reference sets such as
annotation and navigation references sets, but
these are the most common at the moment
SNOMED CT
concept
Clinical finding
Cyanosis
Bronchitis
Vascular
disease
Bronchiolitis
Embolism
Refset
Pulmonary
embolism
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Data Entry
Content coverage
Specificity
One concept with multiple descriptions
SNOMED CT
ICD-10-AM
Five concepts
One code
| 29774004 Vascular myelopathy |
G95.1 Vascular myelopathies
| 432249006 Infarction of spinal cord |
Includes:
| 39134007 Haematomyelia |
-Acute
infarction of spinal cord
-Haematomyelia
-Oedema
| 65605001 Oedema of spinal cord |
| 83982007 subacute necrotic
myelopathy |
of spinal cord
-Subacute
necrotic myelopathy
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communication
Standard terminology across the system
Unambiguous concept identification
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Retrieval
Can utilise all SNOMED CT features to assist with
retrieval for planning, reporting, research
Standard terminology ensures ‘apples are
compared with apples’ no matter where data
sourced from
This is where the power of SNOMED CT can really
be realised
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Example
ICD-10-AM
Diseases of the Respiratory
System
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Influenza and Pneumonia
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J12.9 – Viral Pneumonia, NEC
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J12.9 – Viral Pneumonia,
unspecified
SNOMED CT-AU
ICD-10-AM
Disorder
Diseases
of respiratory system
Pneumonia
Viral pneumonia
of respiratory system
Influenza’s and Pneumonia
Viral Pneumonia
Infectious
diseases
Inflammatory disorders
Infection by sites (lung etc)
Viral infections
Respiratory conditions that have had
related procedures
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CT uses its hierarchies and
attributes to allow retrieval queries to be
written
ICD
was developed to quantify and fund
inpatient events which it will continue to
do
 Longer
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term
Used with decision support
Drive evidence based medicine
Drive clinical process improvement
Facilitate knowledge management
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of these benefits are for
the future
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order to reap the benefits
we need to get SNOMED CT
into systems NOW
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It is not a standalone solution
It needs to be deployed IN a clinical software
application
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SNOMED CT is one part of an EHR product
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The other half is the clinical application itself and
its information model
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Information models define the data entry boxes
(names)
Terminology defines the values which can be
selected and recorded within those boxes
(values)
Diagnosis:
Information
model
Viral Pneumonia
Terminology
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Natively – get SNOMED CT into the backend of
clinical systems
Need to find a balance between using reference
sets to isolate content or using searching
functionality
Recommend reduce dependence on reference sets
and mappings by improving Searching
Functionality
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Only provide search results for current concepts
Don’t return Fully Specified Names
Use the Australian Language Reference Set to
extract relevant descriptions (US spellings out)
Use ‘contains any word’ parameters rather than
‘starts with’
Ensure frequently selected concepts return to the
top of the search results list
Do Not provide pick lists if there are more than ~8
to choose from
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Provide options to browse the hierarchy around a
selected concept
Utilise indexing tables
The better the searching functionality, the larger
your reference set can be without affecting
usability
Realise that improvements here may take some
time to implement – but this is definitely the way to
go!!!
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Options are:
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Natively (with basic searching criteria)
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Use Mappings ..(more on this later)
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Steps to implement into a specific
data element
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Understand your information model data element
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What is the definition of the data element?
What use cases does it need to cover?
Where in the record is it used?
What other data elements sit next to it?
Adverse reaction substance:
Substance that is responsible for a
reaction in a patient
Adverse reaction manifestation:
Adverse reaction type:
Reaction experienced by patient
The type of reaction determined by the clinician
Adverse reaction substance:
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Does
Does
Does
Does
this
this
this
this
include
include
include
include
Substance that is responsible for a
reaction in a patient
medications?
foods?
organisms?
chemicals?
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Understand the context of the information that will
be captured in the data element
◦ Often relates to the SNOMED CT top-level
hierarchies:
Clinical finding
Specimen
Observable entity
Procedure
Organism
Substance
Event
Social Context
Body Structure
Situation with
explicit context
Pharmaceutical or
Australian Medicines
Terminology Product
Adverse reaction substance:
Substance that is responsible for a
reaction in a patient
AMT Product/ Pharmaceutical Biologic
hierarchy
‘Pepzan’
‘Brolene eye drops’
Substance hierarchy
‘penicillin’
‘latex’
Clinical finding hierarchy
‘allergy to penicillin’
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Identify terminology content
Get to know the SNOMED CT hierarchies and where
different kinds of concepts can be found
Search based on your use cases
Are there any existing codesets you can use as a
source list
Identify content that is NOT valid as well as what is
Document the reasoning used for your decisions
Identify if any existing reference sets can be used
or cut down
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Build your reference set
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Methods will vary based on tools
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NEHTA CTI methods include
 Source data method
 Attribute method
 Concept enumeration method
 Simple inclusion method
More information can be found in the
‘Development approach for reference sets’
document in the SNOMED CT-AU Release
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Unpack reference sets – technical processes
Use Australian language reference set
Ensure searching functionality works
Test it
Two distinct types
1. From local terms and codesets TO SNOMED CT
2. FROM SNOMED CT to other instruments (ICD for eg)
 Different purposes
 Different methods
 Different outcomes
Type 1
Mapping codesets to SNOMED CT are
- Prone to information loss
- Expensive to build and
- Require ongoing maintenance and review
- Recommend the use of a mapping as a
migration tool
Type 1
Should be regarded as migration
 Take the old termset content
 Map it once, properly, to SNOMED CT content (RefSet?)
 And then ‘switch’ to the SNOMED CT for continued use
Similar approach to the upgrade and switch over from:
 Analogue to digital television signal service
 Leaded to unleaded to E10 petrol
For instance: Emergency Department Reference Set
Example:
1234 | Chronic bronchitis migrates to
Old termset content
mapped to
63480004 | Chronic bronchitis
SNOMED CT content
Type 2
Perceived as semi-automation of traditional ICD coding
More accurately regarded as transformation
Take SNOMED CT content
Find suitable ICD candidate
Include ICD rules – NOTE INCLUDES, EXCLUDES, NOS,
NEC
Assign ICD-10 code for use in reporting
CONCEPTID
111613008
SNCT DESCRIPTION
Closed skull
fracture with
intracranial injury
(disorder)
MAP GROUP
1
2
MAP ADVICE
ALWAYS S06.90
ALWAYS S02.90
TARGET CODE
ICD DESCRIPTION
S06.90
Intracranial injury,
unspecified, without
open intracranial
wound
S02.90
Fracture of skull and
facial bones, part
unspecified, closed
Try under a different name or wording
Contact the service desk
([email protected])
Submit a request submission to NEHTA
([email protected])
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Acknowledge challenges and the journey to
implementation that we all face
Thanks and any Questions?
[email protected]