1. IHTSDO Observables Project Group April 21, 2008 Evanston, Illinois
Exploration of Possible Concept Models for Observable Entities Revised based on discussion
IHTSDO Observables Project Group
April 21, 2008
Evanston, Illinois

2. Examples of Observables
Histologic type = ? (carcinoma, adenoca,…)
Tumor site = ? (lung, brain, …)
Ability to hear = ? (able, unable, …)
Serum sodium level = ? (N, Abn, 129mg/dl)
Pupil size = ?(N, large, small, 9mm, …)
Total body water (amount) =?(x…)
Response to sound
Hearing examination
No! This is a procedure

3. Agreement based on prior discussions:
Measurement procedures are different from the observable that they measure
More generally, observation procedures are different from the entities they observe

4. A draft model for observables
Organize the observable entity hierarchy using attributes similar to the current measurement procedure attributes
Use existing COMPONENT, PROPERTY, TIME ASPECT, and SCALE TYPE
Change domain from Measurement procedures to Observables
Expand and revise allowable value domains
Replace HAS SPECIMEN with SYSTEM (perhaps keep HAS SPECIMEN as a role hierarchy sub-role of SYSTEM)
Permit anatomical sites, body substances, as well as specimens
Replace MEASUREMENT METHOD with TECHNIQUE (perhaps keep MEASUREMENT METHOD as a role hierarchy sub-role of TECHNIQUE)
Create a new techniques value set
Move to their own hierarchies, separate from observables:
functions
processes
activities
Allow functions, processes, activities also to be values of COMPONENT (in addition to substances, organisms, cell structures)
Do not allow observables to be values of COMPONENT

5. SYSTEM / OBSERVABLE SITE
DRAFT model of observables
Observable entity
COMPONENT
Substances, functions, processes, activities, organisms, cell structures
PROPERTY
Properties
SYSTEM / OBSERVABLE SITE
Specimens, Sites
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

6. SYSTEM / OBSERVABLE SITE
Example (1): ability to hear (observable)
Ability to hear
COMPONENT
To hear (function)
PROPERTY
Ability
SYSTEM / OBSERVABLE SITE
Specimens, Sites
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

7. Example (2): blood hemoglobin concentration
Blood Hb concentration
COMPONENT
Hemoglobin
PROPERTY
Concentration
SYSTEM / OBSERVABLE SITE
Blood
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

8. Example (3): Right Pedal pulse (observable)
R Pedal Pulse
COMPONENT
Systemic arterial pulse
PROPERTY
detectability
SYSTEM / OBSERVABLE SITE
Right dorsalis pedis artery
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
Palpation

9. Example (4): Ability to see red-green (observable)
COMPONENT
Red-green color vision (function) = to see red-green
PROPERTY
Ability
SYSTEM / OBSERVABLE SITE
Specimens, Sites
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

10. Example (5): Knee-jerk deep tendon reflex briskness (observable)
Knee-jerk reflex briskness
COMPONENT
Knee-jerk reflex
PROPERTY
briskness
SYSTEM / OBSERVABLE SITE
? Patellar tendon
? Quadriceps muscle
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

11. SYSTEM / OBSERVABLE SITE
Example (6): Head circumference (observable)
(option 1)
Head circumference
COMPONENT
Substances, functions, processes, activities, organisms, cell structures
PROPERTY
Circumference
SYSTEM / OBSERVABLE SITE
Head
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

12. Example (6): Head circumference (observable) (option 2)
COMPONENT
Circumference
PROPERTY
Distance (linear dimension)
SYSTEM / OBSERVABLE SITE
Head
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

13. Example (6): Head circumference (observable) (option 3)
COMPONENT
Head
PROPERTY
Distance (linear dimension)
SYSTEM / OBSERVABLE SITE
Patient
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

14. Alternative model
Use “observable property” as the top level of a hierarchy characterized by properties (also known as qualities), which can have locations etc.
PROPERTY, COMPONENT and SYSTEM rolled into a single value

15. independent continuant
DRAFT alternative model of observables
Observable entity
PROPERTY
properties
INHERES IN
independent continuant
PROPERTY FUNCTION
function
PROPERTY SUBSTANCE
substances
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

16. Example (1): ability to hear (observable)
PROPERTY
ability (property)
INHERES IN
Subject’s auditory system
PROPERTY FUNCTION
To hear (function)
PROPERTY SUBSTANCE
substances
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

17. Example (2): blood hemoglobin concentration
Blood Hb concentration (observable)
PROPERTY
Concentration (property)
INHERES IN
Subject’s intravascular blood
OF FUNCTION
functions
OF SUBSTANCE
hemoglobin
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

18. Example (3): Right Pedal pulse (observable)
PROPERTY
detectability
INHERES IN
Right dorsalis pedis artery
PROPERTY FUNCTION
Systemic arterial pulsation
PROPERTY SUBSTANCE
substances
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
palpation

19. Example (4): ability to see red-green (observable)
PROPERTY
ability (property)
INHERES IN
visual system
PROPERTY FUNCTION
To see red-green (function)
PROPERTY SUBSTANCE
substances
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

20. stretch reflex (deep tendon reflex)
Example (5): Knee-jerk deep tendon reflex briskness (observable)
Observable entity
PROPERTY
briskness
INHERES IN
Quadriceps muscle
PROPERTY FUNCTION
stretch reflex (deep tendon reflex)
PROPERTY SUBSTANCE
substances
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

21. Example (6): Head circumference (observable)
Observable entity
PROPERTY
circumference
INHERES IN
head
PROPERTY FUNCTION
function
PROPERTY SUBSTANCE
substances
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

22. Values for PROPERTY
Top levels of value hierarchy – determined by empirical
analysis of values in the observables hierarchy
Detail
Dimension
Feature
Fluid property
Force property
Location
Quantity
Ratio
Result
Stage
Temperature
Time
Velocity
Wave property

23. dimension [2] (possible: size)
observable entity property kind
dimension [2] (possible: size)
area [20]
distance (synonym: linear dimension)
breadth [20]
circumference [27]
depth [7]
diameter [31]
height [29]
length [42]
width [11]

24. Replace MEASUREMENT METHOD with more general TECHNIQUE
Proposal:
For observation and evaluation procedures, the METHOD (with values from the action hierarchy) represents the goal or objective of what is done: evaluation, testing, imaging, measurement, examination
observation techniques define the observable, via TECHNIQUE (with values from a value set that includes lab techniques and other specific measurement and evaluation actions, such as inspection, palpation, percussion, auscultation)
Techniques are the means by which the action is carried out, not the intended outcome.
Techniques include specific measurement techniques such as Enzyme-linked immunosorbent assay (ELISA).
Need to examine whether this works for procedures other than evaluations, i.e. can we make the distinction between METHOD (means) and TECHNIQUE for all procedures

25. Possible use of observables
An observable can represent the object (in the linguistic sense) of a measurement or observation
May serve as value for OBSERVATION OF attribute of a measurement or observation procedure
An observable can take values to form a finding
Serves as value for the INTERPRETS attribute of a clinical finding.

26. Options for Observation Procedures
Link observation procedures to observables via a new attribute OBSERVATION OF
Procedure : OBSERVATION OF = observable OR
2. Define observation procedures via a series of attributes (COMPONENT, PROPERTY, SYSTEM, TIMING, SCALE, TECHNIQUE) which also defined the observable that is observed.
In this case, the connection from observation procedure to observable is inferable but has no populated attribute.

27. Modeling procedures using OBSERVATION OF
For measurement procedures (observation procedure), the main attributes are
METHOD = measurement – action
OBSERVATION OF = (observable entity)

28. Option 1: with “OBSERVATION OF”
Observation procedure
METHOD
observation G
OBSERVATION OF
Observable entity
COMPONENT
Substances, functions, processes, activities, organisms, cell structures
PROPERTY
Properties
SYSTEM / OBSERVABLE SITE
Specimens, Sites G
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

29. Option 2: no observable intermediary
Observation procedure
METHOD
observation
COMPONENT
Substances, functions, processes, activities, organisms, cell structures
PROPERTY
Properties
SYSTEM / PROCEDURE SITE
Specimens, Sites G
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

30. Options for Observation Findings
Link observation findings to observables via existing attribute (INTERPRETS)
Finding : INTERPRETS = observable OR
2. Define observation findings via a series of attributes (COMPONENT, PROPERTY, SYSTEM, TIMING, SCALE, TECHNIQUE) which also define the observable that is observed.
In this case, the connection from observation finding to observable is inferable but has no populated attribute.

31. SYSTEM / OBSERVABLE SITE
Option 1: with “INTERPRETS”
Clinical finding
HAS INTERPRETATION
value G
INTERPRETS
Observable entity
COMPONENT
Substances, functions, processes, activities, organisms, cell structures
PROPERTY
Properties
SYSTEM / OBSERVABLE SITE
Specimens, Sites G
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

32. Option 2: no observable intermediary
Clinical finding
HAS INTERPRETATION
value
COMPONENT
Substances, functions, processes, activities, organisms, cell structures
PROPERTY
Properties
SYSTEM /
FINDING SITE
Specimens, Sites G
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
techniques

33. Pedal pulse Pedal pulse palpable HAS INTERPRETATION palpable COMPONENT
PROPERTY
intensity
SYSTEM /
FINDING SITE
Dorsalis pedis artery G
TIME ASPECT
Time aspects
SCALE / UNITS
Scale types, units
TECHNIQUE
palpation

34. Examples Right pedal pulse (observable)
Right pedal pulse present (finding)
Palpation of right pedal pulse (procedure)

35. Right pedal pulse present FINDING SITE
HAS INTERPRETATION
palpable G
INTERPRETS
Right pedal pulse (Observable entity)
COMPONENT
Systemic arterial pulse G
PROPERTY
palpability
SYSTEM
Right dorsalis pedis artery
TECHNIQUE
palpation

36. Right pedal pulse present FINDING SITE (SYSTEM)
HAS INTERPRETATION
palpable
COMPONENT
Systemic arterial pulse G
PROPERTY
palpability
SYSTEM (FINDING SITE)
Right dorsalis pedis artery
TECHNIQUE (FINDING METHOD)
palpation

37. Palpation of right pedal pulse Observable entity
OBSERVATION OF G
METHOD
observation - action
PROCEDURE SITE
COMPONENT
Systemic arterial pulse G
PROPERTY
palpability
SYSTEM
Right dorsalis pedis artery
TECHNIQUE
palpation

38. Palpation of right pedal pulse
METHOD
observation - action
PROCEDURE SITE / SYSTEM
COMPONENT
Systemic arterial pulse G
PROPERTY
palpability
SYSTEM / PROCEDURE SITE
Right dorsalis pedis artery
TECHNIQUE
palpation

39. Right pedal pulse present FINDING SITE
HAS INTERPRETATION
palpable G
INTERPRETS
Palpation of right pedal pulse
Observable entity
OBSERVATION OF G
METHOD
observation - action
PROCEDURE SITE
COMPONENT
Systemic arterial pulse G
PROPERTY
palpability
SYSTEM
Right dorsalis pedis artery
TECHNIQUE
palpation

40. Role composition Can be used to link findings to sites via observables
INTERPRETS ο SYSTEM → FINDING SITE
findingX: INTERPRETS = observableY
AND
observableY: SYSTEM [OBSERVABLE SITE] = siteZ
IMPLIES
findingX: FINDING SITE = siteZ
Example:
absent R pedal pulse (finding): INTERPRETS = R pedal pulse (observable)
R pedal pulse (observable): SYSTEM = R dorsalis pedis artery (body structure)
absent R pedal pulse (finding): FINDING SITE = R dorsalis pedis artery (body structure)

41. Role composition
Can be used to link procedures to sites via observables
OBSERVATION OF ο SYSTEM → PROCEDURE SITE DIRECT
procedureX: OBSERVATION OF = observableY
AND
observableY: SYSTEM [OBSERVABLE SITE] = siteZ
IMPLIES
procedureX: PROCEDURE SITE DIRECT = siteZ
Example:
Measurement of head circumference: OBSERVATION OF = head circumference (observable)
Head circumference (observable): SYSTEM = head structure (body structure)
Measurement of head circumference: PROCEDURE SITE DIRECT = head structure (body structure)

42. Additional examples

43. Measurement of substance in system
Lab test finding
HAS INTERPRETATION
value G
INTERPRETS
Measurement of substance in system
observable
OBSERVATION OF G
METHOD
measurement - action
COMPONENT
substance
PROPERTY
concentration
SYSTEM / OBSERVABLE SITE
system

44. Below lower limit of reference range
Low serum sodium
HAS INTERPRETATION
Below lower limit of reference range G
INTERPRETS
Measurement of serum sodium concentration
Serum sodium concentration
OBSERVATION OF G
METHOD
measurement - action
COMPONENT
sodium
PROPERTY
concentration
SYSTEM / OBSERVABLE SITE
serum

45. of ability to see red-green Ability to see red-green (observable)
Red-green color blind
HAS INTERPRETATION
unable G
INTERPRETS
Observation
of ability to see red-green
Ability to see red-green (observable)
OBSERVATION OF G
METHOD
observation - action
COMPONENT
To see red-green (function)
PROPERTY
ability

46. Ability to hear (observable)
Hearing impaired
HAS INTERPRETATION
impaired G
INTERPRETS
Observation
of ability to hear
Ability to hear (observable)
OBSERVATION OF G
METHOD
observation - action
COMPONENT
To hear (function)
PROPERTY
ability

47. Lateralization of observations
Four options for the concept on which to place LATERALITY=side
FINDING-SITE body structure value
Observable
Observable-SYSTEM body structure value
Observable-COMPONENT value
Requires LATERALITY to apply to functions

48. able to hear on the right side HAS INTERPRETATION able
INTERPRETS
Ability to hear (observable)
FINDING SITE
Lateral auditory system (? Ear)
LATERALITY
right
COMPONENT
To hear (function)
PROPERTY
ability

49. able to hear on the right side
HAS INTERPRETATION
able G
INTERPRETS
Ability to hear
COMPONENT
To hear (function)
PROPERTY
ability
LATERALITY
Right

50. able to hear on the right side HAS INTERPRETATION able
INTERPRETS
Ability to hear
COMPONENT
To hear on a side (function)
LATERALITY
right
PROPERTY
ability

51. able to hear on the right side Has-interpretation able
Interprets
Ability to hear
Component
To hear (function)
Property
ability
SYSTEM / OBSERVABLE SITE
lateral auditory system
laterality
right

52. Impact on procedure models
METHOD and TECHNIQUE need to be differentiated
This may be possible by differentiating:
Means
Objective
Need

53. MON* analysis Procedures can be described in terms of their
Means: how they were done
Objective/goal: what was the result intended
Need: motivation for the procedure
*Shortening of the MOAN Acronym credited to Angelo Rossi Mori

54. Modeling procedures Means: Objective/goal: Need:
Currently modeled with METHOD:
incision, excision, etc
Objective/goal:
Also currently modeled with METHOD
Repair, fixation, imaging
Need:
Modeled with HAS FOCUS
Dysfunction, pain, disease

55. Modeling observations
Means:
New: TECHNIQUE (an attribute of a procedure or an observable)
Objective/goal:
Modeled with METHOD, using goal-type actions such as testing, imaging, evaluation, measurement
Need:
Modeled with HAS FOCUS

56. Examples (1) Microscopic urinalysis (procedure)
Determining the contents of a urine specimen by microscopy
METHOD = inspection – action
HAS OBSERVABLE = contents of urine determined by microscopy
Contents of urine determined by microscopy (observable)
TECHNIQUE = microscopy
SYSTEM = urine specimen
COMPONENT = multiple (cells, casts, crystals, microorganisms, …)
PROPERTY = Presence or identity

57. Examples (2)
Measurement of serum Borrelia antibody by ELISA (procedure)
METHOD = measurement
OBSERVATION OF = serum Borrelia antibody (observable)
Borrelia antibody (observable)
PROPERTY = concentration
COMPONENT = Borrelia antibody (substance)
SYSTEM = serum
TECHNIQUE = Enzyme Linked Immunosorbent Assay

59. Models rejected

60. Observation procedure
Clinical finding
Interprets
Observation procedure
Component
Observable entity
Component
Function

61. Red-green color blind (finding)
Observation of ability to see red-green (procedure)
Interprets
Ability to see red-green (observable)
Component
Red-green color vision (function)
Component