Nomenclatures in e-Health Drs. Sven Van Laere Nomenclatures in e-Health

Personal Sven VAN LAERE 4rd year PhD Previous Research in nomenclatures in eHealth systems in Belgium related to pharmacy Promotor: Prof. Dr. M. Nyssen Previous MSc in Engineering: Computer Science (2013) Professional Bachelor in Applied Informatics (2010)

Content Table Definition Clinical ideas History Nomenclatures in e-health “Coding”

Definition Nomenclature Definition Nomen - name Calare - to call A system of names used in a science, as of  anatomical structures or biological organisms

Clinical idea Clinical idea comprise everything we think we know about health, illness, prevention, investigation, and treatment Clinical ideas are the building blocks of a personal health record Connected clinical ideas are essential for a connected health service

Clinical idea? Diseases Organisms Operations Procedures Devices Drugs Part of the body …

Working with clinical ideas Anyone involved in delivering healthcare Recognition, manipulation and interconnection of clinical ideas is a necessary part of the practice of any clinical discipline Growth of knowledge requires new clinical ideas to be developed, expressed and tested Effective delivery of high-quality health care requires clinical ideas to be shared in ways that… Enhance the quality of the patient care Facilitate the growth of clinical knowledge Demonstrably deliver value to money Avoid errors of commision or ommission Clinical decision support

Problem It seems very simple Clinical ideas are important We need to share them What’s the problem? Hasn’t this problem already been solved? Can coding help to this?

Background Example: coronary heart disease Coding is needed Variety of representing a clinical concept Example: coronary heart disease Diagnosis of myocardial infarction Raised cardiac enzymes Myocardial ischaemia Tripple vessel coronary artery disease … Coronary heart disease is the name given to the disease process called artherosclerosis that causes the smooth inside lining of the coronary arteries to become narrowed by fatty deposits, sometimes called 'plaques' or 'artheroma'.

Why Need for a uniform way of expressing Audit NLP has not reached the point where free text can be automatically turned into codes Scientific research Clinical decision support …

History – Text based records 1970 – floppy disk invented IBM introduced a pilot system in GP practice in Exeter, UK 1976 – inktjet printer invented, VHS video tape introduced ICL launched GP system in Otterly St Mary, Exeter, UK 1980: Text based patient records stored on mainframe computer expensive pilot project Patient records linked by landlines Free text allowed users to express clinical ideas Easy for data entry Problem with retrieval

History – Flags to indicate clinical ideas 1982 – compact disks first released New Abies computer system System allowed each practice to specify a set of 96 important clinical ideas and link them to a patient record Shared codes for each practice?

History – Coding clinical ideas 1983 – Lotus 1-2-3 spreadsheet arrived Memory got a bit cheaper Dated coded entries are added to the system The codes are symple mnemonics with no structure Links between similar ideas? => Still hard to query the data

History – Organising clinical ideas 1984 Read Codes released (named after James Read) Hierarchical set of codes Retriaval based on hierarchy

History – Organising clinical ideas 1986 – late 1990’s there was a wider use of clinical systems using coded data Read codes in the UK, SNOMED in the US, ICD-9 classification codes in several countries The scope of coverage was broadening according to scientific improvements Codes served a useful purpose and continued to be used However growing awareness of limitations in simple approaches to codes and hierarchies

History – Organising clinical ideas 1986 – late 1990’s there was a wider use of clinical systems using coded data Read codes in the UK, SNOMED in the US, ICD-9 classification codes in several countries The scope of coverage was broadening according to scientific improvements Codes served a useful purpose and continued to be used However growing awareness of limitations in simple approaches to codes and hierarchies

Limitations to code-based hierarchies In a code-based hierarchy errors cannot be corrected without changing the code Either the hierarchy stays “wrong” or the code must change For example The read code hierarchy suggest that otis media is a type of “nervous system and sense organ disease” F: Nervous system and sense organ disease F5: Ear disease F52: Suppurative and unspecified otitis media

Limitations to code-based hierarchies Suppurative otitis media (middle ear infection) is not a disorder of the nervous system The condition is not a disorder of the nerves or sensors of the ear The middle ear belongs anatomically to the respiratory tract Logically middle ear infections are a type of respiratory tract infection F: Nervous system and sense organ disease F5: Ear disease F52: Suppurative and unspecified otitis media

Limitations to code-based hierarchies Idea of polyhierarchy popped up A simple hierarchy is a tree Every node has one parent node Exception: Most upper parent node (concept) Example Suppurative acute otitis is… (POLYHIERARCHY) An ear disease An infectious disease F: Nervous system and sense organ disease F5: Ear disease F52: Suppurative and unspecified otitis media

Limitations to code-based hierarchies Need for non-hierarchical relations Suppurative otitis media Is caused by “bacteria” but … is not a type of bacteria Occurs in the “middle ear” but … is not a type of middle ear F: Nervous system and sense organ disease F5: Ear disease F52: Suppurative and unspecified otitis media

ICPC International Classification of Primary Care Author: WONCA Int. Class. Committee Two versions: 1987: ICPC-1 1998: WHO (accepted within WHO)

ICPC structure bi-axial One axis: 17 chapters with an alpha code based on body systems/problem areas Second axis: 7 identical components, with rubrics bearing a two-digit numeric code

ICPC’s 17 chapters A General and unspecified B Blood, blood forming organs, lymphatics, spleen D Digestive F Eye H Ear K Circulatory L Musculoskeletal N Neurological P Psychological R Respiratory S Skin T Endocrine, metabolic and nutritional U Urology W Pregnancy, childbirth, family planning X Female genital system and breast Y Male genital system Z Social problems

ICPC’s components Symptoms and complaints 1-29 Diagnostic and preventive procedures 30-49 Treatment procedures, medication 50-59 Test results 60-61 Administrative 62 Referral and other reasons for encounter 63-69 Diseases: 70-99 - infectious diseases - neoplasms - injuries - congenital anomalies - other specific diseases

ICPC example Heartburn Code: D03 Chapter D: Digestive Component 1: Symptom / Complaint Pneumonia Code: R81 Chapter R: Respiratory Component 7: Disease

Read Codes Set of clinical codes designed for Primary Care to record the every day care of a Patient Used in United Kingdom Developed by Dr James Read (GP, Loughborough) Recognized standard for General Practice Hierarchical structure

Key aspects of Read Codes Sorted into categories and chapters Hierarchical structure Combination of letters and numbers CaSe-SeNsItIve Version 1: Maximum of 4 characters (1983) Version 2: Maximum of 5 characters (1985)

Read Code chapters Diagnoses Processes of Care Medication Codes all begin with a capital letter e.g. H33 (Asthma), C10E (Type 1 diabetes mellitus) Processes of Care Codes all begin with a number Used to record history, symptoms, examinations, tests, screening, operations and patient administration, etc e.g. 44P (Serum cholesterol), 65E (Influenza vaccination) Medication Codes all begin with a small case letter Automatically entered into the patient record when any treatment is prescribed e.g. bu25 (Aspirin 75mg tablets)

Read Code chapters Example: C Endocrine, nutritional, metabolic and immunity disorders C1 Other endocrine gland diseases C10 Diabetes mellitus C10E Type 1 diabetes mellitus C10E7 Type 1 diabetes mellitus with retinopathy Could refer to these as “families” of codes – Parent and Child Codes C10 is a parent code to C10E. It is also a child code to C1 Each code begins the same way as the one before but contains an extra layer of detail This pattern repeats across all chapters Enables data to be entered at the required level of detail

Read version 3, Clinical Terms 1994: CTv3 Read version 3, clinical terms Clinical Terms version 3 Intention: develop terminology that could include specialist practice Used in small minority in UK Merged with SNOMED => SNOMED CT

ICD International Classification of Diseases (and Health Related Problems) Long history and many revisions Possibly suffixes CM: Clinical Modifications (e.g. ICD-9-CM) PCS: Procedure Classification System (e.g. ICD-10-PCS) The ICD-9-CM is based on the ICD-9 but provides for additional morbidity detail and is annually updated on October 1 ICD-10-PCS was developed by CMS for use in the U.S. for inpatient hospital settings

ICD End 2014- begin 2015: step-over to ICD-10 Start in Belgium: January, 2015

SNOMED In 1965 SNOP was developed by the College of American Pathologists (USA) Next 50 years several changes on … … the number of concepts … the covered domains … the underlying representation formalism… Result: Systematized Nomenclature of Medicine, Clinical Terms (SNOMED CT) released in 2002

SNOMED CT Controlled coded clinical terminology for use in Electronic Health Records Helps in adding meaning to the EHR SCT maintained and distributed by the IHTSDO since 2007

Fully Specified Name (FSN) SNOMED CT Concept components Concepts Descriptions Relationships CONCEPT Fully Specified Name (FSN) Identifier

SNOMED CT Concept Description types Own unique identifier Numeric identifier of up to 18 digits Used to refer between concepts Description types All concepts have … At least one fully specified name At least one synonym

CONCEPT 80146002 Language refsets Preferred terms

SNOMED CT Relationships Each concept is associated with other concepts by a set of relationships Expressing the defining characteristics of a concept CONCEPT is a subtype of CONCEPT CONCEPT [attribute] has value

SNOMED CT Relationships Subtype relationships Create a hierarchy linking each concept to more general concepts Enable retrieval of specific concepts in response to general concepts

All the supertypes of appendectomy

SNOMED CT Relationships Attribute relationships Provide additional defining information about concepts Why is it different from its supertype E.g. sites, causative agents, …

SNOMED CT Pre- and post-coordination Pre-coordination 31978002 Terminology producer provides a single conceptid for the meaning 31978002 means “fracture of tibia”

SNOMED CT Pre- and post-coordination Post-coordination A user composes a combination of conceptids to represent the meaning 31978002 : 272741003 = 7771000 (fracture of tibia : laterality = left) In human readable form … “fracture of left tibia”

SNOMED CT Which one is best to use? ?

SNOMED CT Which one is ‘best’ to use? Pre-coordination Post-coordination PRO’s CON’s - Single term use - Short vocabulary: each concept once - Terms are easier to understand - Syntax is linked to semantics - Overuse of terms - Long uninterpretable strings - Need for powerful engine (complex)

Relationship All included in UMLS ICD9 ICPC ICD10 UMLS: Unified Medical Language System All crossed with Snomed-Ct

“Coding” Code… Classification… Nomenclature… … is a representation applied to a term so that it can be more readily processed. Classification… … is an arrangement of all elements of a domain, into groups according to established criteria. Nomenclature… … is an arrangement of concepts, that can be combined according to specific rules to form more complex concepts. 2005, S. De Ludignan: Codes, classifications, terminologies and nomenclatures

+ logical groupings (…is a… relationship) “Coding” Codes + logical groupings (…is a… relationship) Classifications + polymorphism + characteristics Nomenclatures

ICPC Codes Read Classifications ICD Nomenclatures SNOMED CT

Sources Papers Presentations Videos 2005, S. De Ludignan: Codes, classifications, terminologies and nomenclatures 2006, R. Cornet: A framework for characterizing terminological systems Presentations IHTSDO: Why Clinical Terminology Matters Health Informatics: Terminology and classification Videos What is ICD 10? https://www.youtube.com/watch?v=ZPDgtDDTc8k