SNOMED CT Search & Data Entry
Fadi El-Turk
Anne Randorff Højen
1
Who are we?
Fadi El Turk
Anne Randorff
•

•
•
•
B.Sc. M.Sc.
Research Consultant at Cerner
2013/2014 SIA Scheme
participant
Previously worked at BMJ
Group
M.Sc., PhD
 Aalborg University, Denmark
 Member of I&I Since 2012
• 2013/2014 SIA Scheme
participant
2
Agenda

Welcome and introduction

Why search and data entry is important (Anne)

Examples of Search and Data Entry techniques (Fadi and Anne)
3
WHY IS SEARCH AND DATA ENTRY
TECHNIQUES IMPORTANT?
4
Why are search and data entry techniques important?
- SNOMED CT is comprehensive and complex
5
The expectation:
SNOMED CT can support
- Semantic interoperability
- Improved efficiency of clinical care
- Effective clinical documentation
- Advanced data analysis
- Automated decision support Meaningful Health Records
Benefit Individuals
- Etc.
Meaningful Health Records
Benefit Populations
ANALYSIS
It is a prerequisite that:
• SNOMED CT codedTREATMENT
data is sharable
and comparable
• Search and data entry capabilities are intuitive,
Meaningful Health Records Support
effective and efficient
Evidence-Based Healthcare
RESEARCH
(Clinical knowledge)
The Problem:
Different strategies  different results
Different results  coding variability
Interrater variability  reduced ability to…
-
Semantic interoperability
Improved efficiency of clinical care
Effective clinical documentation
Advanced data analysis
Automated decision support
Etc.
[Rogers, Jeremy, and Olivier
Bodenreider. "SNOMED CT:
Browsing the Browsers." KR-MED.
2008.]
EXAMPLES OF BROWSER
DIFFERENCES
8
‘low back pain’
9
‘pain lower back’
10
The Problem:
Different strategies  different results
Different results  coding variability
Interrater variability  reduced ability to…
-
Semantic interoperability
Improved efficiency of clinical care
Effective clinical documentation
Advanced data analysis
Automated decision support
Etc.
CONSISTENT CONCEPT SELECTION
A CHALLENGE IN SNOMED CT IMPLEMENTATION
Configuration
of EHR
CONSISTENT CONCEPT SELECTION
A CHALLENGE IN SNOMED CT IMPLEMENTATION
•
•
•
•
Attention must be focused on the consistent
application of SNOMED CT.
Concept selection needs clear and extensive
rules.
Necessary to know the content and structure
of SNOMED CT.
Tooling is important, e.g. more sophisticated
browsers.
Configuration
of EHR
1.
CHIANG, Michael F., et al. Reliability of SNOMED-CT coding by three physicians using two terminology browsers.
In: AMIA Annual Symposium Proceedings. American Medical Informatics Association, 2006. p. 131.
2.
ANDREWS, James E.; RICHESSON, Rachel L.; KRISCHER, Jeffrey. Variation of SNOMED CT coding of clinical
research concepts among coding experts. Journal of the American Medical Informatics Association, 2007, 14.4: 497-506.
3.
VIKSTRÖM, Anna, et al. Mapping the categories of the Swedish primary health care version of ICD-10 to SNOMED CT
concepts: Rule development and intercoder reliability in a mapping trial. BMC Medical Informatics and Decision Making,
2007, 7.1: 1-9.
The Problem:
Different strategies  different results
Different results  coding variability
Interrater variability  reduced ability to…
Reduced ability to...
-
Semantic interoperability
Improved efficiency of clinical care
Effective clinical documentation
Advanced data analysis
Automated decision support
Etc.
The new IHTSDO ‘Search and Data entry Guide’





Provides recommendations on
Search and Data Entry
Techniques
Developed as part of the
‘SNOMED CT Implementation
Advisor Scheme 2013’
Reviewed by the I&I committee
Currently under final review by
the Head of Implementation
and Education
To be published by the end of
April
16
Target Audience of the guide
End users of search and
data entry
Implementers of
search and data entry
functionality
?
!
17
Search vs. data entry
18
Search use cases
Learning about the structure of the terminology
Creating reference sets (e.g. to represent subsets of terms and concepts)
Creating templates and protocols for data entry
Creating queries to retrieve data
Reviewing terminology content
Data entry
19
Search guidance
Search by words and Identifiers
Constrain searches
Extend searches
Improve search speed
Optimize display of search results
20
Data entry guidance
SNOMED CT and structured records
Requirements for entry and display of SNOMED CT
Constraining data entry
Entering refinements for postcoordinated expressions
21
EXAMPLES OF SEARCH
TECHNIQUES
22
SEARCH BY WORDS AND
IDENTIFIERS
23
Search by words
 String searches must be user configurable to support
searches, such as searching for:
 words any order
 phrase match
 identical term
Filter by
Search box
Search results
ventral hernia
ventral hernia
obstructed ventral hernia
obstructed ventral hernia
recurrent ventral hernia
recurrent ventral hernia
irreducible ventral hernia
irreducible ventral hernia
ventral hernia with gangrene
Phrase match
Go
Words – any order
Phrase match
Identical term
Starts with
Ends with
24
Search by identifiers – Searching for cold (1)
25
Search by identifiers – Searching for cold (2)
26
Search by identifiers – Searching for cold (3)
27
Search by identifiers - by Concept ID
28
Search by identifiers - by Description ID
29
CONSTRAIN SEARCHES
30
Constrain search and data entry by
hierarchy

Constrain searches by supertype ancestors (e.g. Disorder)
1
Filter by
Search box
renal calculus
Search results
renal calculus
calyceal renal calculus
calcium renal calculus
O/E: renal calculus
history of renal calculus
uric acid renal calculus
calculus in renal pelvis
on examination - renal calculus
O/E: cystine renal calculus
Disease
Go
Procedure
Disorder
Clinical Finding
Results found: 30
2
Filter by
• Recommended as a user
configurable option for most use
cases
Search box
renal calculus
Search results
renal calculus
calyceal renal calculus
calcium renal calculus
O/E: renal calculus
uric acid renal calculus
calculus in renal pelvis
on examination - renal calculus
O/E: cystine renal calculus
O/E: oxalate renal calculus
Disorder
Results found: 13
31
Go
Constrain search and data entry by
hierarchy
32
Constrain search and data entry by reference sets
 Language ref sets to avoid uncommon or foreign terms
 Simple ref sets to simplify or encourage selection of
concepts or used in a particular country, organization, or
specialty
 Context ref sets to specify or order the valid Concepts for
entry in a particular field
33
Constrain search and data entry by reference sets
34
ANNE  FADI
35
Constrain search by status

Constrain searches by Concept and Description status
Filter by
Search box
Search results
ventral hernia
ventral hernia
obstructed ventral hernia
obstructed ventral hernia
recurrent ventral hernia
recurrent ventral hernia
irreducible ventral hernia
irreducible ventral hernia
ventral hernia with gangrene
Active status
Go
Active status
Inactive status

Constraining by active Concepts is recommended for data entry use
cases
 There are a few use cases where a user may legitimately wish to
search Inactive Concepts and Descriptions (e.g. creating queries for
diagnoses for retrospective research).
36
Constrain searches to avoid multiple hits on the same concept
Display
Search box
Search results
hernia
herniated structure
hernia
herniated tissue
herniated structue
herniation
Fully specified name
Go
Fully specified name
Synonym
37
EXTEND SEARCHES
38
Extend searches – Use Word Equivalents (1)

In healthcare, there are many words with equivalent meanings
 Synonyms provide alternative phrases referring to the concept
 Synonyms are not created automatically for every possible
combination of words with an equivalent meaning
‘Renal calculus’ is a synonym of ‘kidney stone’
Search for ‘kidney stone fragmentation’  ‘Percutaneous nephrostomy with
fragmentation of kidney stone’ result
Search for ‘renal stone fragmentation’  no results.
Extend searches – Use Word Equivalents (2)
One way of addressing this problem is to maintain a table of Word
Equivalents
1
2
40
Extend searches: by post-coordinated searching (1)

When typing text for a search, the user is unlikely to know if their
intended entry can be represented by a single Concept or requires a
post-coordinated expression involving additional Concepts or
qualifiers.

Where searches fail to find a pre-coordinated match, expansion of
the search to support appropriate or commonly used qualifiers is
likely to enhance usability.
41
Extend searches: by post-coordinated searching (2)
1
2
42
IMPROVING SEARCH SPEEDS
43
Improve search speeds
 Enable real time searching
 Show an indication of estimated number of matches
before starting a search
 Allow slow searches to be paused or cancelled
 Optimize indexing
44
OPTIMISING THE DISPLAY OF
SEARCH RESULTS
45
Order Search Results Rationally (1)
 Order shortest matching results first
Search box
hernia
Search results
hernia
hernia
hernia sac
hernia truss
hernia belt
cecal hernia
hernia repair
pudendal hernia
sciatic hernia
Go
Shortest description
Longer description
46
Order Search Results Rationally (2)
 Order preferred term matches before synonyms
Search box
hernia
Search results
P hernia
S hernia
P hernia sac
P hernia belt
S hernia truss
P hernia repair
S hernia cerebri
P hernia adiposa
P hernia of ovary
Preferred
term
Synonym
Go
47
Order Search Results Rationally (3)
 Order user preferred language matches first in
multilingual environments
48
Order Search Results Rationally (5)
 Display search results with most frequently used
descriptions listed first
1
2
Search box
hernia
Search results
P hernia
S hernia
P hernia sac
P hernia belt
S hernia truss
P hernia repair
S hernia cerebri
P hernia adiposa
P hernia of ovary
Go
Search box
Search results
hernia
Go
Frequently searched
S hernia cerebri
----------------------------------------------------S hernia
P hernia
S hernia sac
P hernia belt
P hernia truss
49
Distinguish identical descriptions of different concepts
1
Search box
hernia
Search results
P hernia
S hernia
P hernia sac
P hernia belt
FSN: herniated structure (morphologic abnormality)
S hernia truss
P hernia repair
S hernia cerebri
P hernia adiposa
P hernia of ovary
Go
2
Search box
hernia
Search results
P hernia
S hernia
P hernia sac
P hernia belt
S hernia truss
FSN: hernia of abdominal cavity (disorder)
P hernia repair
S hernia cerebri
P hernia adiposa
P hernia of ovary
Go
50
Rationalize search results by subsumption checking
Before
Search box
hernia
Search results
P hernia
S hernia
P hernia sac
P hernia belt
S hernia truss
P hernia repair
S hernia cerebri
P hernia adiposa
P hernia of ovary
Go
Results found: 413
After
Search box
Search results
hernia
S
Go
hernia
Text
Results found: 1
51
Display navigation results effectively (1)
 Using the subtype hierarchy
Search box
Subtype
hierarchy
hernia
Go
SNOMED CT Concept
body structure
morphologically altered structure
morphologically abnormal structure
mechanical abnormality
protrusion
hernia
complete hernia
hernia adiposa
hernia, reduction en
masse

Not designed for data entry
52
Display navigation results effectively (2)

Using the navigation hierarchy (hand-crafted)
• Navigation hierarchies can be
used to drive some types of
structured data entry
• Navigation hierarchies can order
data in sensible ways by priority,
or by some readily understood
convention (e.g. cranial nerve
order).
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DISCUSSION
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The impact of efficient search capabilities
-
Semantic interoperability
Improved efficiency of clinical care
Effective clinical documentation
Advanced data analysis
Automated decision support
Etc.
Thank you for your attention
Questions?
 Contact IHTSDO: info@ihtsdo.org
 Web site: www.ihtsdo.org
 Anne Randorff Højen:
arra@hst.aau.dk
 Fadi El Turk: Fadi.El-Turk@Cerner.com
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