Desiderata for Controlled Medical Vocabularies

1. Desiderata for ControlledMedical Vocabularies James J. Cimino

2. Background • Attempt to synthesize requirements expressed in the literature for the past decade • Prepared for the IMIA Working Group 6 Jacksonville, Florida, January 1997 • Methods of Information in Medicine, 37(4/5), 1998

3. Desideratum I: Content • Must seek to be provide breadth and depth • Atoms versus molecules • A formal methodology is needed • Structure must not limit size

4. Desideratum II: Concept Orientation • Concepts, not terms • One meaning (nonvague) • No more than one meaning (nonambiguous) • Higher-level ¹ ambiguous • One concept per meaning (nonredundant) • May have multiple context-dependent meanings

5. Desideratum III: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

6. Desideratum IV: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)

7. Desideratum V: Polyhierarchy • Needed for tree walking • Needed for inferencing • Needed for "essence" • Example: diseases of the liver which also involve the kidney

8. Desideratum VI: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

9. NEC

10. NEC

11. Desideratum VII: Reject "Not Elsewhere Classified" • Can never have a formal definition • Vocabulary changes induce semantic drift • There are valid alternatives

12. Desideratum VIII:Multiple Granularities • Different levels for different purposes • Uncertainty is allowed, imprecision is not (we must be precise about our uncertainty)

13. Desideratum IX:Multiple Consistent Views • Multiple views for multiple purposes • Must not lead to inconsistency

14. A C B E D F H G I

15. A C B E D F H G I A C B E F D (G,H) (I)

16. A C B E D F H G I A E D F H G I

17. A C B E D F H G I A C B E D F H G I

18. A C B E F E E D F H G I H G H G I A C B D

19. A C B E D F H G I A C B E D F E H G I

20. A C B E D F H G I A C B E D F E H G I

21. Desideratum X:Representing Context • Needed: a grammar to show usage • "What is sensible to say" • Consider modeling "events"

22. Controlled Medical Vocabulary Definitional Knowledge (how concepts define each other) Pathologic Function Finding Body Site is -a has- site is -a is -a Joint Joint Swelling Swelling is -a has- abnormality Right Knee

23. Controlled Medical Vocabulary Assertional Knowledge Definitional Knowledge (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site modifies is -a has- site Finding Body Site is -a is -a Joint Joint Swelling Swelling is -a has- abnormality Right Knee

24. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee

25. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Electronic Medical Record

26. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Electronic Medical Record

27. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Progress Note Progress Note Progress Note Electronic Medical Record

28. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Progress Note Progress Note Progress Note Electronic Medical Record

29. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Progress Note Physical Exam Progress Note Progress Note Electronic Medical Record

30. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Progress Note Physical Exam Progress Note Progress Note Finding: Electronic Medical Record

31. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Progress Note Physical Exam Progress Note Progress Note Finding: [Joint Swelling] Electronic Medical Record

32. Controlled Medical Vocabulary Contextual Knowledge Assertional Knowledge Definitional Knowledge (how concepts are used) (how concepts combine) (how concepts define each other) Pathologic Function Finding Body Site part-of Physical Exam Finding modifies is -a has- site Finding Body Site part -of is -a is -a Joint Joint Swelling Hospital Progress Swelling is -a Admission Note has- abnormality part-of Right Knee Hospital Admission Progress Note Physical Exam Progress Note Progress Note Finding: [Joint Swelling [Right Knee]] Electronic Medical Record

33. Desideratum XI:Graceful Evolution • Will always need to fix mistakes • Medical knowledge will grow • Bad reasons • Good reasons

34. Desideratum XI:Graceful Evolution • Bad reasons: - Redundancy - Major name changes - Code reuse - Changed codes

35. Desideratum XI:Graceful Evolution • Good reasons: - Simple addition - Refinement - Minor name changes - Precoordination - Disambiguation - Obsolescence - Discovered redundancy

36. Desideratum XII: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"

37. Finding Pneumonia Left Lower Lobe Desideratum XII:Recognize Redundancy

38. Finding Pneumonia Left Lower Lobe Desideratum XII:Recognize Redundancy Left Lower Lobe Pneumonia

39. Finding Pneumonia Left Lower Lobe Desideratum XII:Recognize Redundancy Left Lower Lobe Pneumonia is-a: Pneumonia

40. Finding Pneumonia Left Lower Lobe Desideratum XII:Recognize Redundancy Left Lower Lobe Pneumonia is-a: Pneumonia has-site: Left Lower Lobe

41. Finding Pneumonia Left Lower Lobe Desideratum XII:Recognize Redundancy Left Lower Lobe Pneumonia is-a: Pneumonia has-site: Left Lower Lobe participates-in: Finding

42. Finding Pneumonia Left Lower Lobe Desideratum XII:Recognize Redundancy Left Lower Lobe Pneumonia is-a: Pneumonia has-site: Left Lower Lobe participates-in: Finding

43. Status Report I. Content II. Concept Orientation III. Concept Permanence IV. Nonsemantic Concept Identifiers V. Polyhierarchy VI. Formal Definitions

44. Status Report • VII. Reject "Not Elsewhere Classified" • VIII. Multiple Granularities • IX. Multiple Consistent Views • X. Representing Context • XI. Graceful Evolution • XII. Recognize Redundancy

45. Practical Considerations • Think “Concept Orientation” • Have an editorial policy • Consider explicit definitions • Nonsemantic identifiers • Include “is-a” attribute • Pay attention to maintenance issues • Include data dictionary in terminology • Please: reject NEC!