e-terminologies nomenclatures and classifications for health informations systems in the Internet era A.Rossi Mori,, CNR, Roma

Transcription

1 NursingData, Bern,, e-terminologies nomenclatures and classifications for health informations systems in the Internet era A.Rossi Mori,, CNR, Roma itbm.rm.cnr.it

2 content 1. coding schemes - usage vs distribution 2. terminologies provide labels for situations 3. russian dolls - nesting heterogeneous details 4. semantic patterns - models for a domain 5. diagnoses - actions - resources 6. heterogeneous expressions - MOAN 7. three generations of terminological systems 8. model-based development 2/4/02 2

3 1. coding schemes - usage vs distribution what is a coding scheme coding scheme vs. classification vs. nomenclature basic principles of terminology for health information systems direct usage vs. coding process vs. iterative development interface systems vs. reference system 2/4/02 3

4 coding scheme a coding scheme is made of a set of expressions a set of codes it provides the domain of admitted values for a field in a message (communication) or in a database (documenting and retrieval) the two sets are conceived for a precise task performed by a sub-community of users within their information systems 2/4/02 4

5 need for multiple coding schemes each user performs different tasks and belongs to different sub-communities within overlapping information systems data are used by various professionals need for different levels of granularity different degree of aggregation different criteria for aggregation 2/4/02 5

6 nomenclature vs classification nomenclature - direct use complete and non-redundant set of expression used in actual daily practice (patient record) classification - secondary uses set of classes (grouping standard expressions or defined through description and examples) for statistics or decision-making not directly usable by professionals in patient records use artifacts like NOS, NEC, other 2/4/02 6

7 basic principles 1/3 nomenclatures and classifications are coding schemes plus measures to assist proper usage (e.g. index, systematic presentation,, ) the classsification classsification in ICD is the set of 4-character 4 classes ICD provides also a systematic presentation (the taxonomy) that is not the classification the index of ICD is not a nomenclature 2/4/02 7

8 basic principles 2/3 to assure an overall coherence across tasks, multiple interface coding schemes should be derived from the same reference system by selecting an appropriate subset of entries if needed, providing a new set of codes (with look-up tables for mapping) adapting index and systematic presentation according to criteria conceived for the intended sub-community of users 2/4/02 8

9 basic principles 3/3 each interface coding scheme should be developed to become the domain of admitted values for at least a defined attribute in an information model, i.e. for a field in a database or a message many purposive classifications may be derived from the same nomenclature, according to different criteria 2/4/02 9

10 usage of codes and agreed expressions interface nomenclatures (or local vocabularies mapped to them) for input, storage, transmission interface classifications for processing statistics decision making reimboursement 2/4/02 10

11 distribution of systems interface coding schemes (a table?) index, with synonyms and permutation of words systematic presentation, with hierarchies task-specific specific instructions (e.g. for death certificates) description of intended meaning, inclusions, exclusions, examples knowledge and software for coding assistance 2/4/02 11

12 iterative development and maintenance build the first prototype of a reference system starting from existing interface systems style guidelines for homegeneous decisions,, e.g. same granularity of details across the system coherent shape of expressions, with explicit details collect feedback from actual usage and provide timely updates with tracking for changes do not reuse codes provide an historical database with validity dates for each expression and each code 2/4/02 12

13 from reference to interface systems selection of an appropriate subset of entries for a predefined task (according to skills, environment, goals,, ) developers of reference systems should use richer tools with respect to distribution of interface systems purposive presentation instructions adapted to specific users and tasks index should be adapted to assist intended users to solve current ambiguities within the actual subset of expressions 2/4/02 13

14 2. terminologies provide labels for situations an expression evokes a situation motivated expressions concepts evolve according to tasks coding scheme as a coherent set of appropriate labels for a task regularities within expressions and systematic details 2/4/02 14

15 terminologies as proxy what is an intervention? performing the activity many hours? reporting one document labelling one expression classifying for statistics or resource allocation one classification code a suitable concept replaces many information items e.g. in family history: : just kind of relative ( mother, instead of name, address, age, ) 2/4/02 15

16 motivated expressions a motivated expression represents a unitary unitary concept for a professional Bleeding chronic ulcer of stomach and severe atrophic gastritis with campylobacter but the professional will describe the same situation with a variable emphasis on details according to contexts and communication goals 2/4/02 16

17 a patient record is made of statements terminology catch just a part of the clinical information expressions cover a variable number of details, depending on tasks fragments of a statement can be splitted into multiple variables (database fields) low anterior resection of rectum for lower third rectum cancer with double stapling technique without temporary colostomy 2/4/02 17

18 concepts evolve according to tasks 1/2 admission operation for lower third rectum cancer booking the operating room low anterior resection of rectum or abdominoperineal amputation of rectum (Miles operation) documenting the surgical operation low anterior resection of rectum with double stapling technique discharge summary ICD-9-CM CM 48.63: other anterior resection of rectum 2/4/02 18

19 concepts evolve according to tasks 2/2 request for reimboursement operation for rectum cancer, DRG 147 cost analysis anterior resection of the rectum with double stapling technique quality control low anterior resection of rectum without temporary colostomy and operation for lower third rectum cancer 2/4/02 19

20 different kinds of details ACTION LESION ANATOMY METHOD removal of a tumor of lower third rectum low anterior of rectum resection abdomino-perineal of rectum amputation low anterior resection of rectum double stapling technique other anterior resection of rectum operation for tumor of rectum anterior resection of rectum double stapling technique low anterior resection of rectum without temporary colostomy operation for tumor of lower third rectum 2/4/02 20

21 who will use a complete expression (?) each motivated expression presents only the details useful with respect to the evolution of care process and the goal of the information exchange the complete expression would have been low anterior resection of rectum for lower third rectum cancer with double stapling technique without temporary colostomy but it will never appear in a real patient record! 2/4/02 21

22 flexibility vs. usability users expressive needs: countless motivated expressions processing needs: a limited number of coherent and meaningful expressions compromise: a coding scheme must be able to resist against the user s tendency of adding uncontrolled details A TOLERABLE LEVEL OF EXHAUSTIVENESS 2/4/02 22

23 features of coding schemes 1/3 classification for statistical use - reduce individual variability of clients - limited number of classes (to have an adequate number of cases in each class) nomenclature to represent client s data - large number of expressions, rich of details registered expressions = compromise among - flexibility - expressive power - number of predefined elements that the system is able to manage 2/4/02 23

24 features of coding schemes 2/3 multiaxial compositional systems (e.g. SNOMED) user can build expressions (dissections) from simple elements (descriptors) a phrase = sequence of codes maximal flexibility and expressiveness usage of descriptors for information retrieval but 2/4/02 24

25 features of coding schemes 3/3 negative aspects of a compositional system: - allows for non-meaningful combinations - code sequences are of variable lenght - an expression may be coded by different sequences (jeopardising comparisons and queries) SNOMED 3: joins nomenclatures for diseases and activities with a multiaxial system to add further details LOINC, OMED: constraints on admitted combinations 2/4/02 25

26 complementary coding schemes - statistics classifications, assessment scales: staging, grading - management of clinical information systems systematic nomenclatures, controlled vocabularies - agreement on the meaning of terms dictionnaires, glossaries - reimboursement of procedures and services price lists - indexing and retrieval of cases, papers, protocols, books,, web pages thesauri 2/4/02 26

27 appropriateness of coding schemes intended application defines: 1. the style to build entries 2. the degree of flexibility within the system abuse: : ICD (WHO s( classification for diseases) initially conceived for mortality statistics, adapted for hospital morbidity misused as nomenclature for patient records co-existence of various coding schemes must be promoted (one for each application) distributed as a super-system system with multiple functionalities 2/4/02 27

28 3. russian dolls - nesting heterogeneous details typology of details various kinds of contexts: abstract description of a typical situation instantiation of a situation within an event documenting the event transmitting the documentation details for terminologies and details for various patient record fields: a developer s pragmatic decision 2/4/02 28

29 nesting details and contexts we need a systematization and clear names for the different kinds of contexts which detail goes in which context? which details must be considered by a coding scheme? base concept (e.g. kind of disease or procedure) operational details (e.g. device, challenge,, site) status concepts (e.g. severity, certainty, negation, state, mood, risk) instantiation context (when, where, how many,, ) attribution context (e.g. author, language, confidentiality) envelope (e.g. sender, receiver) 2/4/02 29

30 different kinds of information base concept focus of the expression operational details essential features status concepts semi-terminological aspects instantiation related to the event when, where, who, why, duration, repetition,, attribution related to documenting author,, date of recording, confidentiality envelope related to transaction sender, receiver, dates of transaction 2/4/02 30

31 canonisation of semantic fragments base concept 1 0..* terminological details 1 kernel fully described expression 1 situated expression 1 clinical statement 1..* payload status concept 1..* instantiation context (actual event) 1 attribution context (description) 1 transaction unit envelope 1 a theoretical model from a clinical point of view, NOT the way to represent multiple statements in messages or documents 2/4/02 31

32 semantic features vs. processing fragments from a clinical point of view pure semantic perspective underlying thesaurus - a systematic list of the reasonably isolable kinds of fragment intrinsic regularities within a coding system, independent of use cases and potential utilisation fragments from an application point of view units that are worthwhile processing there is a frequent/relevant need for usage of a kind of fragment (=attribute) in most applications, according to use cases 2/4/02 32

33 4. semantic patterns - models for a domain regularities within an expression the grammar to construct an expression semantic pattern behind an expression modelling a domain 2/4/02 33

34 ontology of actions, semantic patterns drug-related related activity acts on has feature is cause of has temporal marker is stopped because immunization activity uses prevents medicinal product commercial category, provision category complication, side effect, adverse reaction timing marker clinical situation vaccine pathologic condition information and education activity has topic clinical situation is directed to person 2/4/02 34

35 elementary actions in ICNP 1/3 observing identifying determining monitoring assessing tracing, profiling examining, testing, analyzing, checking, verifying, measuring, calculating surveying, collecting, supervising interpreting MONITORING = 1. continuous surveillance (one-to to-one, one, one-to to-many) 2. continuous recording, for subsequent analysis 3. daily measurements over a long period 2/4/02 35

36 elementary actions in ICNP 2/3 performing cleaning, grooming, bathing, covering, feeding, positioning, manipulating, mobilizing, stimulating, cutting, suturing, ventilating, preparing, inflating, inserting, installing, removing, changing managing organizing providing coordinating, controlling applying, distributing 2/4/02 36

37 elementary actions in ICNP 3/3 caring assisting treating preventing relating informing teaching guiding describing facilitating, supporting, promoting alleviating, relieving, restoring protecting, avoiding communicating, presenting, collaborating, contracting, praising, comforting, touching instructing, educating anticipatory guiding, advising, counselling recording, documenting 2/4/02 37

38 5. diagnoses - actions - resources an expression for a diagnosis should evoke a typical behaviour an expression for an intervention should evoke a typical scenario of resources (skills, responsibilities,, ) 2/4/02 38

39 diagnoses - actions different expressions of diagnoses must be able to predict / evoke differences in natural evolution, actions,, care plans i.e. to predict potential behaviour of professionals and clients (decisions, interventions) also with respect to physician s diagnosis 2/4/02 39

40 actions - resources different expressions of actions must be able to predict / evoke differences in usage of resources intensity (e.g. one-to to-one), one), reaction time (scheduled( scheduled,, on alarm,, ) devices, skills, duration, intellectual /practical activity responsibility / autonomy of decisions, cooperation with others, role of client / family, 2/4/02 40

41 classify 1. arrange expressions into classes, homogeneous with respect to the predictions according to a purpose (co-existence of multiple taxonomies, for different purposes) 2. assign a case to a class within an actual information system (traditionally, classes were conceived for statistical purposes) 2/4/02 41

42 reference vs. interface vs. taxonomy reference system complete list of allowed expressions interface systems subset of expressions used to assign cases in a particular environment (kind of facility, specialisation of provider,, ) taxonomy predefined arrangement of expressions from reference or interface systems into homogeneous classes for a particular task 2/4/02 42

43 6. heterogeneous expressions - MOAN style guidelines must assist developers to produce homogeneous expressions taxonomies should be build according to generic relations the MOAN effect on healthcare actions could produce heterogeneous taxonomies 2/4/02 43

44 MOAN and heterogeneous expressions same situation, different levels of explanation Means Operational Achievements Need connect circuit turn on switch turn on lamp remove darkness only the operational level is actually performed by the actor 2/4/02 44

45 MOAN vs. generic relations MOAN relations aren t generic (parent/child)) relation as associative relations (many( to many) jeopardise terminological processing Means Operational Achievements Need insert a balloon fix obstruction revascularisation avoid hypoxia 2/4/02 45

46 <needs> > are not <actions> pain management prevention of falls are useful titles for sections of textbooks or patient records <needs> > do not provide information about the actual intervention performed pattern: intervention triggered by <diagnosis> 2/4/02 46

47 DANGER: heterogeneous taxonomies to get rid of a stone surgical removal litotripsy how to produce isoresources classes? administer medication injection oral administration dressing 2/4/02 47

48 7. three generations of terminological systems 1G - traditional paper-based systems 2G - computer-assisted development one model-based reference system with many interface systems multiaxial, compositional multiple specialised classifications built according to various criteria 3G - computer-based processing formal systems 2/4/02 48

49 three generations of terminological systems 1. Traditional terminological systems enumerated lists, optionally with hierarchies and modifiers 2. Compositional systems based on categorial structures and cross-thesauri 3. Formal systems formalism + model + software engine 2/4/02 49

50 FIRST GENERATION: traditional terminological systems presentation: systematic list (typically( with codes), alphabetical index with permutations organisation: fixed; typically one (hierarchical) plus modifiers purposes: devoted to a single application 2/4/02 50

51 FIRST GENERATION: traditional terminological systems flexibility and extension: NO; pre-defined list of allowed expressions (plus modifiers) processing on semantics: NO; only storage, transmission and retrieval of strings and codes 2/4/02 51

52 categorial structures and thesauri: the idea of dissection "flexible colonoscope" could be expressed by the dissection: instrument that PERFORMS: examination, removal(specimen, <pathology< pathology>) HAS TARGET: colon HAS FLEXIBILITY: flexible the dissection is made of descriptors according to a pattern for coding assistance, indexing and systematic naming 2/4/02 52

53 categorial structure: an example on <medical devices> criteria related to the intended purpose performs: <device function>, <healthcare< procedure> has target: <body component>, <pathology< pathology>, <age < group>, <personal role>, <organism< organism>, <medical device> has context of use: <specialty>, <localization< localization> criteria related to the intrinsic features is based on: <technical principle> has constituent: <material>, <device < component> is presented as: <presentation form>, <physical< state> non-systematic specifications has specification: <sterility type>, <power source type>, <temporal type>, <reusability < type>,... 2/4/02 53

54 cross-thesaurus: an example on <medical devices> category examples of descriptors <device function> drainage, dilatation, scanning <healthcare procedure> angioplasty, catheterization <body component> airway, chest, skin,, plasma, saliva <body function> respiration, circulation,, vision <pathology> fracture, hernia, aneurism, polyp <personal role> patient,, nurse, physician,, staff <age group> infant, newborn, adult, fetus <localization> patient's home, hospital <technical principle> fluorescence,, hyperthermia <sterility type> supplied sterile, sterilizable <reusability type> single-use use, disposable, reusable <flexibility type> flexible, rigid /4/02 54

55 four components of a second-generation system 1. categorial structure (semantic categories, semantic links, relevant structural patterns) interim release modest amount of resources in a short time; 2. cross-thesaurus (set of descriptors organized according to the categories in 1.) modest amount of resources to work out most descriptors 3. family of structured lists of classes or phrases lists requires continuous maintenance, phrases require local adaptations; 4. knowledge base of authoritative dissections where each phrase of 3. is represented by descriptors from cross-thesaurus 2., according to structural patterns from 1. 2/4/02 55

56 <action> a potential categorial structure" insertion, excision for a surgical procedure performed on <structure< structure> <body part>, <prosthesis< prosthesis>, <pathological < structure> uses <prosthesis>, <body part> shunt, mammary artery by means of <action tool> surgical laser guided by <visualisation tool> laparoscope,, ultrasound device 2/4/02 56

57 towards 2G super-systems systems classifications, nomenclatures, controlled vocabularies LOINC, DICOM-SDM, SNOMED3, RCC, ICD PCS increased flexibility and compositionality - complex structure, abandon paper-based presentation - presentation: many coding schemes + database + navigation software - more usability (adaptable to tasks) mapping towards a common reference system - facilitates maintenance - inspires more coherence (internally and across schemes) 2/4/02 57

58 the long-term goal: 2G super-systems systems organised according to various criteria semi-automatic generation of taxonomies, model- driven (categorial structures) multi-hierarchical presentation for multiple tasks integration of different coding schemes possibility of extending the list of expressions with user-created expressions (according to composition constraints) 2/4/02 58

59 co-existence and specialisation co-existence of families of coding schemes within the same information system (each scheme is conceived to satisfy a purpose) specialised coding schemes differ by criteria to select the subset of expressions by amount of details - granularity (e.g. classification vs nomenclature) by kind of details (e.g. classifications with various purposes) 2/4/02 59

60 categorial structure (standard model) cross-thesaurus (hierarchies of descriptors) criteria ICNP? multiple hierarchies (taxonomies) present reference lists of classes (purposive classifications) classify interface nomenclature select,extend mapping (once) adapt reference list of actual expressions (nomenclature) local controlled vocabulary 2/4/02 60

61 SECOND GENERATION: compositional systems presentation: categorial structure + cross-thesaurus of descriptors (atoms) + reference list of expressions and multiple purposive interface coding schemes (molecules: classifications, nomenclatures,,...) + knowledge base of authoritative dissections organisation: dynamic (multiple, hierarchical) purposes: multiple flexibility and extension: new atoms can be added by users new combinations can be made by users processing on semantics: clustering of phrases according to criteria; structured extension of lists; extract and rearrange details; structured input interfaces (suggest details) 2/4/02 61

62 THIRD GENERATION: formal systems presentation (internal): universal model + engine by combinatorial rules (parsimonious,, precise) organisation: dynamic (multiple, hierarchical) purposes: multiple flexibility and extension: new combinations validated by computer (by predefined combinatorial rules) processing on semantics: complete (formal( processing) 2/4/02 62

63 synergy across generations 1/2 interface coding schemes (1G), i.e. coherent lists of pre-coordinated entries are still needed for: reimboursement resources assignment appointments / scheduling consultation of knowledge bases (e.g. pointers in a drug database) 2/4/02 63

64 synergy across generations 2/2 development, distribution, coding assistance: a comprehensive 2G super-system system (reference system) usage in patient record, messages, decision making: multiple 1G coding schemes (interface systems) development and maintenance of very large systems, harmonisation across domains and purposes 3G formal systems 2/4/02 64

65 8. model-based development development is iterative parallel refinement of four components: model thesaurus of descriptors (atoms) list of expressions (molecules) set of dissections models and categorial structures may be used to produce systematic names 2/4/02 65

66 development of systems model-based development and refinement initialise an iterative process collect existing sources or a new set of expressions produce an interim model produce an interim thesaurus of descriptors produce interim paraphrases to disambiguate and make explicit details in original expressions perform an analytic test by tentative dissections on a limited set of paraphrases perform a global review - discover regularities and consequences on taxonomies 2/4/02 66

67 development of systems loop on the iterative process collect new expressions discover and fix irregularities in the original sources revise the model revise and systematise the thesaurus of descriptors revise paraphrases according to the current model and the current experience on descriptors perform an adequate number of dissections perform a global review - discover further regularities and consequences on taxonomies 2/4/02 67

68 delimiting meaning 1/3 in most scientific and technical domains, terms are defined by intensional definitions (superordinate concept and differentiating detail) health dictionaries (e.g. Dorland s) provide careful intensional definitions for thousands of words the major challenge for health terminologies is to provide the most complete set of expressions suitable for a task (i.e., a coding scheme) explicit intensional definitions are rare each expression delimits the meaning of the others other measures delimit and clarify the meaning 2/4/02 68

69 delimiting meaning 2/3 systematic names are self-defined names built by standard elementary terms according to precise rules (as in chemistry ) categorial structures and models could assist in the generation of systematic names classes are defined by their content the set of expressions belonging to the class inclusions, exclusions, examples: clarify doubts explicit guidelines and instructions intended meaning may be fixed by a sentence e.g. mental disorders in ICD 2/4/02 69

70 delimiting meaning 3/3 extrinsic definition of concepts interventions described by actions diseases or syndromes described by findings or by reaction to therapy presentation tools systematic presentation (taxonomy) usually provides superordinate concepts often names for children concepts consist only of the differentiating characteristic (i.e. without repeating the name of the superordinate concept) - see ICD index provides guidance with inclusions 2/4/02 70

71 Usage of models 1/3 1. within one terminology system systematic presentation multiple automatic taxonomies discovering ambiguities and imprecisions regularity of children across the system generated compositionally from the same list systematic names automatic generation of purposive subsets 2/4/02 71

72 Usage of models 2/3 2. across terminology systems unified background representation mapping - through the unified representation reduce unnecessary diversity clarify motivated diversity not replacement, but increasing coherence 2/4/02 72

73 Usage of models 3/3 3. terminology vs information system and patient record compare and harmonise models combinatorial code hidden in one field vs set of explicit fields and relations clarify expected content of terminologies negotiate responsibilities select the proper subsets for a field 2/4/02 73

74 inability to cross road < is perspective on dimension ability < is applied to FOCUS crossing road has bearer BEARER < has focus client JUDGEMENT absence Note: the examples do not reflect the latest version of CEN / ISO standards 2/4/02 74

75 change dressing replacing action type has object > OBJECT dressing material has beneficiary has means MEANS BENEFICIARY patient dressing = dressing material 2/4/02 75

76 teaching patient how to take drug teaching has object has beneficiary [patient taking drug] patient patient taking drug = taking drug has object has agent has beneficiary drug patient patient 2/4/02 76

77 teaching patient how to take drug teaching has object has object has agent taking drug drug patient has beneficiary patient has beneficiary patient NESTING ACTIONS 2/4/02 77

78 risk for infection < is perspective on dimension < is applied to has site body component relative position FOCUS timing has location infection < has focus has bearer client BEARER risk for presence JUDGEMENT severity potentiality frequency acuity temporal pattern has etiology environment situation 2/4/02 78

79 presence of pressure ulcer < is perspective on dimension < is applied to has site body component relative position FOCUS timing has location ulcer < has focus has bearer client BEARER presence JUDGEMENT severity potentiality frequency acuity temporal pattern has etiology environment pressure situation 2/4/02 79

80 absence of ability of client about crossing road FOCUS timing has site body component dimension < is perspective on < is applied to crossing road < has focus has bearer client ability absence JUDGEMENT severity potentiality frequency acuity temporal pattern relative position has BEARER location has etiology environment situation 2/4/02 80

81 dressing of pressure sore on patient body component relative position generic activity in the context of < has site applying dressing < has location place has route medication route action type timing frequency temporal pattern has means MEANS by doing has object > pressure sore process OBJECT has beneficiary BENEFICIARY patient 2/4/02 81

82 removal of drain from patient body component relative position generic activity in the context of < has site < has location place has route removing medication route action type timing frequency temporal pattern has means MEANS by doing has object > drain process OBJECT has beneficiary BENEFICIARY patient 2/4/02 82

83 advice to patient about tepid sponging to patient body component relative position generic activity in the context of patient < has site advicing < has location place action type timing frequency temporal pattern has beneficiary tepid sponging has object > OBJECT has route has means medication route MEANS has beneficiary BENEFICIARY patient 2/4/02 83

84 teaching patient how to take drug body component relative position generic activity in the context of < has site < has location place teaching patient action type timing frequency temporal pattern has beneficiary BENEFICIARY has object > has object taking drug has beneficiary drug OBJECT patient 2/4/02 84