Computer-Based Patient Records and Medical Informatics

Standards

Yuval Shahar M.D., Ph.D.

Medical Decision Support Systems

The Medical (Patient) Record

• A historical record of patient care• A communication tool among care providers

• A research and knowledge-gaining tool• A teaching tool• An operational tool (e.g., order entry)

• A business tool (e.g. to support billing)• An administration record (e.g., to manage resources)• A legal record with considerable longevity

Electronic Medical Record (EMR)• AKA: Computer-Based Patient Record (CPR)• Provides multiple advantages vs. manual records:

– Record can be used by multiple personnel at the same time– Record is accessible from anywhere (even from home)– Clear, well-organized, legible documentation– Data can be reused for other purposes– Data can be integrated from multiple sources transparently– Data can be validated automatically– Enables multiple automated research and decision-support

functions (analysis, machine learning and data mining, automated diagnosis, reminders, guideline-based care)

– Decision support can be integrated with use of the patient record

EMR: Costs

• Large initial set-up investments – Hardware, software, training, support,

maintenance

• Significant workflow changes• Significant organizational changes• Difficult data entry relative to handwriting• Potential catastrophic failure

– Note: paper records also have “down” times

Integration of EMR and Decision Support Modules

• Decision support is most effective when integrated with an EMR– The most likely opportunity for providing decision

support is when the physician is assessing the patient record or entering an order

– All or most relevant patient data can be accessible to the DSS and do not require separate entry

– Physician should always be able to override the recommendation and, if relevant, provide feedback

Order Entry

• A major function of an EMR system, allowing care providers to enter clear, legible orders for patient care anytime, anywhere

• Supports validation of order, issuing of alerts, suggestion of relevant information and knowledge, and even actions

• Quick effect on physician ordering behavior

EMR and Knowledge Sources

• The most effective time to provide access to knowledge is when the care provider is browsing the patient record

• A query can be formulated in a context-sensitive manner with respect to the patient record, thus anticipating the physician’s needs– Note: Queries often have relatively expected structure

and content (e.g., which drug is useful for condition X in context Y; What are side effects of drug Z when used in manner W; What clinical guidelines are most relevant for disease D in patients of type P)

EMRs: Major Issues

• Data Entry– Data capture: the scope of the data that is or can be

represented in the EMR– Data input: coded data are difficult to input by

physicians; text is less useful for processing– Errors can be reduced by multiple validity checks

Validity Checks During Data Entry in an EMR

• Range checks (Hemoglobin in [0..30] Gr/Dl)• Pattern checks (a telephone number pattern)• Numeric and other inter-data constraint checks

(total of WBC differential is 100%)• Consistency checks (pregnant male??)• Temporal-abstraction checks (weight cannot

change by 50 Kgs in 2 days)• Spelling checks

Physician-Entered Data

• The main challenge to EMR developers!– Patient histories, physical findings, interpretations,

diagnostic and treatment plans

• Several very different entry methods– Transcription of dictated or written notes– Structured encounter forms from which notes are

transcribed and even encoded– Direct entry of data by physician via computer

• Speech recognition might alleviate some of the difficulties

Security Issues in EMRs

• Authorization– Is my dentist allowed to see my gynecological record?– Which fields of my record can my or another GP view?– Who has asked to view my records last month?

• Authentication– Is this user really my physician?

• Encription– Can an eavesdropper understand the message sent to

my doctor?

• Eventually, security depends on people

The Need for Standards• EMRs and almost any other information-oriented

system in a clinical environment cannot be used without well-defined standards for representing and communicating information

• Data need to be exchanged between multiple, heterogeneous systems and might be used by very different applications

• Standards are needed for several different uses:– Identifying patients, providers, health-care plans,

employers– Transferring patient data across different systems– Representing medical knowledge that can be reused

How are Standards Developed?• Ad hoc

– A group of interested people and organizations agree on an informal specification (ACR/NEMA DICOM)

• De facto– A single vendor creates standard through monopoly (Microsoft

Windows)

• Government mandate– Agency creates a standard and legislates it (HCFA UB92 claim

form)

• Consensus– A group of volunteers work openly to create standard (HL7).

Examples of Information-Standards Organizations

• American National Standards Institute (ANSI)– Private, nonprofit– Accredits organizations that create standards

• Technical Committee 251 (CEN TC 251)– The European Standardization Committee’s technical

committee for medical informatics standards

• American Society for Testing and Materials (ASTM)– Largest non-government source of standards in the USA– ASTM committee E31 is responsible for development of

medical information standards

Terminologies and Controlled Vocabularies

• Precoordinated– All concepts encoded beforehand – no

possibility of creating new terms

• Postcoordinated– New combinations can be formed from existing

terms to describe new concepts

International Classification of Diseases (ICD)

– Intended mostly for talking about dead people (reporting mortality statistics to the WHO)

– Strict hierarchy with core 3-digit codes, possibly 4th digit

– ICD-9 (1977) common; inadequate for clinical reporting– ICD-9-CM (Clinical Modifications) adds extra levels of

details by 4th and 5th digits, popular in USA– ICD-10 (1992) exists, but no clinical modifications yet

Codes in The International Classification of Diseases (ICD-9 CM(

724 Unspecified disorders of the back724.0 Spinal stenosis, other than cervical

724.00 Spinal stenosis, unspecified region724.01 Spinal stenosis, thoracic region724.02 Spinal stenosis, lumbar region724.09 Spinal stenosis, other

724.1 Pain in thoracic spine724.2 Lumbago724.3 Sciatica724.4 Thoracic or lumbosacral neuritis724.5 Backache, unspecified724.6 Disorders of sacrum724.7 Disorders of coccyx

724.70 Unspecified disorder of coccyx724.71 Hypermobility of coccyx724.71 Coccygodynia

724.8 Other symptoms referable to back724.9 Other unspecified back disorders

Diagnosis-Related Groups (DRGs(

• A USA (Yale( abstraction of the ICD-9-CM codes

• A small number of codes grouping multiple diagnosis codes by similar expected costs of hospitalization

• Modifies the major diagnosis by associated conditions, severity, and procedures to determine specific DRG code

Current Procedual Terminology (CPT(

• Encodes diagnostic and therapeutic procedures• Adopted in the USA for billing and

reimbursement

• Similar to DRG, classifies procedures by cost and reasons

• CPT-4: The main code used for reporting physician services to government and private insurance reimbursement

Diagnostic Statistical Manual of Mental Disorders (DSM(

• Published by the American Psychiatric Association

• Provides nomenclature as well as definitions (diagnostic criteria( of psychiatric disorders

• Coordinated with ICD; e.g., DSM-IV is coordinated with ICD-10

Systemized Nomenclature of Medicine (SNOMED(

• Developed by the American College of Pathologists• Evolved from SNOP, A multi-axial system for

describing pathological findings by postcoordination of topographic (anatomic(, morphologic, etiologic, and functional terms

• SNOMED III: 11 axes, more than 130,000 terms• SNOMED-RT (Reference terminology( created to

encourage more consistent use of terms

• Main problem: Too expressive—several ways of defining the same term (e.g. acute appendicitis(

Read Clinical Codes

• Developed by James Read during the 1980s

• Adopted by the British National Health Service (NHS( in 1990

• Version 3 is a multiple hierarchy, and version 3.1 added ability for postcoordination of modifiers

• Work undergoing to map to SNOMED

The Unified Medical Language System (UMLS(

• A project of the National Library of Medicine (within the National Health Institutes [NIH](

• Main resource: The Metathesaurus– contains over 330,000 terms– relates terms from over 40 different sources

• Supports searching the medical literature• Uses Medical Subject Headings (MeSH( which

are used to index medical literature

Logical Observations, Identifiers, Names and Codes (LOINC(

• A naming system developed by McDonald and Huff for tests and observations (now includes also vital signs, ECG, etc(

• Uses six semantic axes to encode the test, such as substance measured (urine( and analysis method used

• Coordinated development with the European Clinical Data Exchange Standard (EUCLIDES( standard

Data Interchange Standards

• Allow a sender to transmit data (a transaction set) to a receiver in unambiguous fashion

• Closely related to the Open Systems Interconnection (OSI) 7-layer communication model of the International Standards Organization (OSI)– Physical, data link, network, transport, session, presentation,

and application (semantic-specification) layers

• Typically use position dependent or tagged field format

Example Data-Interchange Standards

• ACR/NEMA– American College of Radiologists with the National

Electronic Manfacturers Association– Current version: DICOM 3.0; uses an object oriented

model and supports ISO communications

• ASTM E31– Published E1238, Standard Specification for Transferring

Clinical Observations Between Independent Systems– E1460: Defining and Sharing Modular Health Knowledge

Bases is the Arden Syntax for Medical Logical Modules

Health Level 7 (HL7)

• Today, includes more than 500 industrial and academic organizational members and over 1800 individual members

• Name refers to OSI application layer 7• A standard for exchange of data among different

hospital computer applications• Built upon ASTM 1238 and other protocols• Version 3 (1999) is object oriented and uses a

Reference Information Model (RIM)

Functions of a Health-Care Information System (HCIS) (I)

• Patient management– Admission, Discharge, Transfer (ADT)

– Patient tracking

• Departmental management– Ancillary departmental systems support clinical

departments; laboratory, radiology, pharmacy, blood bank and medical records are most commonly automated

• Care delivery and Clinical documentation– Mostly order entry and results reporting

Functions of a Health-Care Information System (HCIS) (II)

• Clinical decision support– Built upon other HCIS components and need to be

integrated with them (e.g. during order entry)

• Financial and resource management– Typically the first functions to be centralized

• Managed-care support– Integrated Delivery Networks (IDNs) start focusing more

on patient health maintenance rather than cutting costs of treating sick patients

– Thus, provider-profiling systems, contract management systems and more sophisticated modules

Three Classic HCISs (1)

• The HELP system at the University of Utah– Developed by Warner et al. at LDS Hospital

– Incorporated decision support logic modules from the start; these react to data and issue reminders, alerts, and advices

– Uses the HELP Frame Language

– Eventually led to Medical Logical Modules and the Arden Syntax

Three Classic HCISs (2)

• The Center for Clinical Computing (CCC) system at Beth Israel Deaconess Medical Center– Developed by Bleich and Slack as a centralized system in

Beth Israel Hospital, Boston from 1978– Intensively used– Includes knowledge access to MedLine via the PaperChase

module, as well as email– Ambulatory system supports problem lists and clinic notes– Uses a MUMPS database, used as the clinical-data

repository, and the ClinQuery online data warehouse– Very little decision-support functionality

Three Classic HCISs (3)

• The DIOGENE System at Geneva Canton University Hospital– Developed by Jean-Raoul Scherer and colleagues from

1971– Migrated from a centralized to distributed architecture– Supports all administrative and clinical functions– Reports are printed; physicians write orders by

telephoning an operator who types the order while physician dictates, views typing on computer screen, and gives verbal consent.