Desirable Clinical Terminology Characteristics and Present Adherence

James J. Cimino

Defining the Need for a Controlled Vocabulary

• Recording primary clinical information

• Multipurpose (re-use)

• Sharing data

• Maintenance

1: Content

• Must seek to be provide breadth and depth

• Atoms versus molecules

• A formal methodology is needed

• Structure must not limit size

2: Concept Orientation

• Concepts, not terms

• One meaning (nonvague)

• No more than one meaning (nonambiguous)

• Higher-level ambiguous

• One concept per meaning (nonredundant)

• May have multiple context-dependent meanings

3: Concept Permanence

• Old concepts can't be deleted

• Example: non-A-non-B hepatitis

• Names can be changed as long as meaning doesn't change (retronyms)

• Example: transvenous pacemaker

4: Nonsemantic Concept Identifiers

• Don't use the name

• Don't use a code that will run out of room

• Don't use a hierarchical code

• Meaningless integer (+/- check digit)

5: Polyhierarchy

• Needed for tree walking

• Needed for inferencing

• Needed for "essence"

• Example: diseases of the liver which also involve the kidney

6: Formal Definitions

• Support understanding

• Support maintenance

• Structured and controlled (not narrative)

• Represented through relationships within the vocabulary

• Defintional versus assertional knowledge

• Additional effort minimal and will pay off

NEC

NEC

7: Reject "Not Elsewhere Classified"

• Can never have a formal definition

• Vocabulary changes induce semantic drift

8: Multiple Granularities

• Different levels for different purposes

• Uncertainty is allowed, imprecision is not

• We must be precise about our uncertainty

9: Multiple Consistent Views

• Multiple views for multiple purposes

• Must not lead to inconsistency

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D E F(G,H) (I)

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10: Representing Context

• Needed: a grammar to show usage

• "What is sensible to say"

• Consider modeling "events"

Controlled Medical Vocabulary

Definitional Knowledge(how concepts define each other)

Body Site

Joint

is -a

Finding

JointSwelling

PathologicFunction

Swelling

is -a is -a

Right Kneeis -a

has-abnormality

has-site

Controlled Medical Vocabulary

Definitional Knowledge(how concepts define each other)

Assertional Knowledge(how concepts combine)

Body Site

Body Site Findingmodifies

Joint

is -a

Finding

JointSwelling

PathologicFunction

Swelling

is -a is -a

Right Kneeis -a

has-abnormality

has-site

Controlled Medical Vocabulary

Definitional Knowledge(how concepts define each other)

Assertional Knowledge(how concepts combine)

Contextual Knowledge(how concepts are used)

Body Site

Body Site FindingFinding Physical Exam

ProgressNote

HospitalAdmission

part-of

part -of

part-of

modifies

Joint

is -a

Finding

JointSwelling

PathologicFunction

Swelling

is -a is -a

Right Kneeis -a

has-abnormality

has-site

Electronic Medical Record

Controlled Medical Vocabulary

Definitional Knowledge(how concepts define each other)

Assertional Knowledge(how concepts combine)

Contextual Knowledge(how concepts are used)

Body Site

Body Site FindingFinding Physical Exam

ProgressNote

HospitalAdmission

part-of

part -of

part-of

modifies

Hospital Admission

Progress Note

Progress Note

Progress Note

Physical Exam

[Joint Swelling [Right Knee]]

Joint

is -a

Finding

JointSwelling

PathologicFunction

Swelling

is -a is -a

Right Kneeis -a

has-abnormality

has-site

11: Graceful Evolution

• Will always need to fix mistakes

• Medical knowledge will grow

• Bad reasons

• Good reasons

11: Graceful Evolution

• Bad reasons:

- Redundancy

- Major name changes

- Code reuse

- Changed codes

11: Graceful Evolution

• Good reasons:

- Simple addition

- Refinement

- Precoordination

- Disambiguation

- Obsolescence

- Discovered redundancy

- Minor name changes

12: Recognize Redundancy

• Synonyms are good• Redundant concepts are bad• Redundant expressions are inevitable• Example:

- Year 1: "Pneumonia", "Left Lower Lobe"

- Year 2: "Left Lower Lobe Pneumonia"

12: Recognize Redundancy

Pneumonia

Finding

Left Lower Lobe

12: Recognize Redundancy

Left Lower Lobe Pneumonia Pneumonia

Finding

Left Lower Lobe

12: Recognize Redundancy

Left Lower Lobe Pneumonia is-a: Pneumonia

Pneumonia

Finding

Left Lower Lobe

12: Recognize Redundancy

Left Lower Lobe Pneumonia is-a: Pneumonia has-site: Left Lower Lobe

Pneumonia

Finding

Left Lower Lobe

12: Recognize Redundancy

Left Lower Lobe Pneumonia is-a: Pneumonia has-site: Left Lower Lobe participates-in: Finding

Pneumonia

Finding

Left Lower Lobe

12: Recognize Redundancy

Left Lower Lobe Pneumonia is-a: Pneumonia has-site: Left Lower Lobe participates-in: Finding

Pneumonia

Finding

Left Lower Lobe

What's Here Today?

1: Content

4: Nonsemantic Concept Identifiers

8: Multiple Granularities

10: Multiple Consistent Views

What May Be Here Soon?

2: Concept Orientation

3: Concept Permanence

5: Polyhierarchy

6: Formal Definitions

7: Reject "Not Elsewhere Classified"

What's Left?

10: Representing Context

11: Graceful Evolution

12: Recognize Redundancy

Keep Your Eye on the Goal

• Recording primary clinical information

• Multipurpose (re-use)

• Sharing data

• Maintenance