Concept Model for observables, investigations, and observation results For the IHTSDO Observables Project Group and LOINC Coordination Project Revision Date: March 14, 2014 Part-1

Integrating situations, conditions, observables and observation results We have adopted “situation” as the meaning of the clinical findings hierarchy Situation (definition): – A phase of life of the subject during which he/she is the bearer of a clinical condition Clinical condition (definition): – A subject-related body process, disposition, or (patho-)anatomical structure, which is reportable in the context of health records.

Integrating situations, conditions, observables and observation results Some of the content of the current |Clinical finding| hierarchy does not fit the situation definition – These meanings need to be separated out (moved, or perhaps retired and re-created) into a different hierarchy (or hierarchies) – observation results are not situations They are information artifacts that are the output of observation procedures

observation result It is proposed that the results of observations should be placed under a top-level category that is distinct from situations. – Yet to be determined: will observation result be a subtype of a new “information artifact” top level? Or will there be no “information artifact”, but rather “observation result” will be a top level concept.

Integrating the models of situations, conditions, and observation results 1.Place the current |Clinical finding| hierarchy under a new |Situation| hierarchy. 2.Place observation results in their own hierarchy 3.Remove “interprets” and “has interpretation” attributes from current model – Terms that record that something has been observed to be (or interpreted to be) increased, decreased, normal or abnormal are considered observation results

Observable, observation procedure, observation result It is proposed that these all have closely- coordinated models observation procedure – Uses most of the same attributes as observable, and adds method=evaluation action observation result – Uses most of the same attributes as observable, and adds has value

Concept model attributes: OBSERVABLE ENTITY Current (none) Proposed property type inheres in (location,ingredient) towards characterizes (agent, duration, output) relative to (part of) precondition scale units technique direct site informer

observable entity scale scale types Combined models for | observable entity | and | observation procedure | units technique techniques direct site material entities property type property types independent continuants inheres in towards independent continuants precondition precondition values material entities (inherent) location substances (inherent) ingredient processes characterizes material entities process agent time frames process duration substances process output relative to substances (rel-to) part of independent continuants is about quality or property observation procedure specified by observes informer subjects

observable entity scale scale types Observable for qualities units technique techniques direct site Material entities property type property types independent continuants inheres in towards Independent continuants precondition Precondition values Material entities (inherent) location substances (inherent) ingredient relative to substances (rel-to) part of Independent continuants is-about quality observation procedure specified-by informer subjects observes specified-by ○ observes ⊑ is-about

observation result is about property / quality output of observation procedure observable entity observes specified by

observation result is about property / quality output of observation procedure observable entity observes specified by

observation result is about property / quality output of observation procedure observable entity observes specified by

observable entity property type property types scale scale types partly “flattened” model for ‘quality’ observables independent continuants inheres in towards functions, substances units technique techniques is about precondition body states (challenges, fasting) direct site body structures, specimens quality inherent location material entities inherent ingredient substances informer subjects

observable entity property type property types scale scale types completely “flattened” model for ‘quality’ observables independent continuants inheres in towards functions, substances units tehnique techniques precondition body states (challenges, fasting) direct site body structures, specimens inherent location material entities inherent ingredient substances informer subjects

observable entity scale scale types Model for process observables units technique techniques direct site material entities property type property types independent continuants inheres in towards independent continuants precondition precondition values material entities (inherent) location substances (inherent) ingredient processes characterizes material entities process agent time frames process duration substances process output relative to substances (rel-to) part of independent continuants is about property of process observation procedure specified by observes informer subjects

Observable for processes (the “is about” part of the model) property type precondition characterizes process agent process duration process output property of process observable entity is about

Concept model attributes: CLINICAL FINDING Current associated with associated morphology finding site pathological process occurrence has definitional manifestation clinical course episodicity severity Proposed (situation includes condition) associated with associated morphology site pathological process occurrence has definitional manifestation clinical course episodicity severity

clinical finding has definitional manifestation Clinical finding / disorder (current) occurrence finding method finding informer finding site associated morphology episodicity pathological process associated with &/subs severity clinical course interprets has interpretation laterality G G

situation has definitional manifestation Clinical finding / disorder -> situation includes (structure, process, disposition) occurrence finding method finding informer site associated morphology episodicity pathological process associated with &/subs severity clinical course interprets has interpretation laterality G G

Concept model attributes: CLINICAL FINDING (2) Current finding informer finding method interprets has interpretation Proposed -> observation result

Concept model attributes: OBSERVATION RESULT Current finding informer finding method interprets has interpretation Proposed informer technique observes has value units scale

Concept model attributes: MEASUREMENT procedure Current method = measurement action property has specimen scale type time aspect measurement method component Proposed – observation procedure method = evaluation action property type direct site scale process duration technique towards + inheres in + precondition units informer

observation result scale scale types observation result units technique techniques direct site material entities property type property types independent continuants inheres in towards independent continuants precondition precondition values material entities (inherent) location substances (inherent) ingredient processes characterizes material entities process agent time frames process duration substances process output relative to substances (rel-to) part of independent continuants is about quality or property observation procedure output of observes informer subjects has value

observation result scale scale types observation result for a quality units technique techniques direct site material entities property type property types independent continuants inheres in towards independent continuants precondition precondition values material entities (inherent) location substances (inherent) ingredient relative to substances (rel-to) part of independent continuants is about quality observation procedure output of observes informer subjects has value

observation result scale scale types observation result for property of a process units technique techniques direct site material entities property type property types precondition precondition values processes characterizes material entities process agent time frames process duration substances process output is about property of process observation procedure output of observes informer performer of observation / subject has value

observation result scale ordinal left knee jerk reflex 2+ out of 4+ (observation result) units technique techniques direct site left knee/patellar tendon property type briskness of response precondition precondition values knee jerk reflex (process) characterizes material entities process agent time frames process duration substances process output is about property of process observation procedure output of observes informer performer of observation / subject has value ++ out of ++++

Presence, absence Proper description logic representation of the presence or absence of a condition should be represented using the object property includes: “situation and includes some condition” and “situation and not includes some condition” – The OWL 2 EL profile does not provide negation. ‘Situation which does not include condition’ concepts will have to be primitive in a module that is based on EL or else these absence concepts will need to be separated into a module that is classified using a reasoner that can handle a profile that includes negation

observation result An information artifact – Is-about some observable – Has-value some {value}

observation result model (1) – This model makes a distinction between the target of an observation – the thing the observation is about - such as an inherent quality or independent continuant that is being observed – and any aspects of the act of observation that defines the observation – Two parts of the observables model: – A) the quality/property part of the model: This models the thing being observed, which is the intended object of the observation – This part of the model deals with real entities that exist independent of being observed – B) the observation procedure part of the model: This models the defining characteristics of the observation act – This part of the model deals with the various characteristics that define the type of observation that is done, such as technique, units, time scale, etc. These characteristics may also help us infer how we know, and how accurately we know, that the object of observation has the characteristics that are observed. The defining characteristics of the observation act are ontological with respect to acts of observation. Some people have called these “epistemological” and declared them out of bounds for an ontology, but this is a misunderstanding of what observables are about. These features are only out of bounds for an ontology of the targets of observation, but not out of bounds for “observables” as intended to be covered with this proposed model.

observation result model (2) – uses a nested expression or pre-coordinated named dependent quality (or other type of entity) to represent what is being observed Note: there is a difference between “what is being observed” and “what the thing observed is a quality of” E.g. “color of skin”: What is being observed is color. The color happens to be a quality of skin, which might happen to have a particular location. – we assume only one set of observation characteristics per act of observation – If the results of an observation are multiple, then the model requires that there be multiple individual observations. – observation result is a replacement for the name “finding” for those entities (including things already represented in SNOMED CT that have the tag “finding”) that fit this model.

observation result model (3) What does this model do to existing measurement procedure attributes? – Replaces HAS SPECIMEN with direct site – The direct site is the immediate direct locus of the observation action (as opposed to the exact locus of the quality that is intended to be measured or assessed) and is available to be used when the entity that is being directly observed is not at the same locus as the intended object of the observation. (The intended object of the observation is the entity in which the observed property inheres; or the independent continuant which is ideally intended to be observed). – Replaces measurement method with technique – Not all observations of interest are measurements, and “measurement method” is too close a name to “method” which takes values from the action hierarchy to define procedures in SNOMED CT. – There is a new techniques hierarchy from which the values will be drawn – Revises and changes the configuration of COMPONENT, PROPERTY, SYSTEM – COMPONENT and SYSTEM – Replaced by inheres in and towards. These are expected to achieve better reproducibility via clearer ontological definitions. – property type – Retains current properties and adds values related to PATO (ontology of qualities) – scale TYPE – Retains scale TYPE in the observation part of model, and adds units to coordinate with IFCC-IUPAC. – TIME ASPECT – Eliminates TIME ASPECT from quality type observations because they are necessarily present at a single point in time; adds process duration for processes – Moves to their own hierarchies, separate from observables: functions processes activities – Allows functions, processes, activities also to be values of towards (in addition to substances, etc) – Does not allow observables to be values of inheres in or towards.

observation result model (4) – Differentiates between a dependent quality per se and a property type. – Concentration is a property type. – The concentration of sodium in serum is a dependent quality. – Renames PROPERTY to property type

observation result model (5) – Deprecates the use of “absence” as a property type – Asserting absence of findings/functions/abilities/etc. requires negation (using a modification of the situation model). – Observables would also not use “associated morphology” But note: Conditions can be modeled using “associated morphology” with a value that implies physical absence of a structure that is normally present E.g congenital atresia, traumatic acquired absence – Deprecates the use of “presence” as a property type. – Presence is necessarily implied by conditions modeled with associated-morphology, but presence is not a property type for observables E.g supernumerary structure (morphologic abnormality) implies presence of an extra structure not normally present.

The observation part of the model Continued in Part-2 of slide deck Main attributes are: – scale – units – technique – direct site