Health-tech glossary

ADT messages are the HL7 v2 messages a hospital system sends when a patient is registered, admitted, transferred, discharged or has their details updated (A01, A03, A08 and about fifty more events).

AllergyIntolerance is the FHIR resource for a patient's allergy or intolerance: the substance (coded), whether it is an allergy or intolerance, criticality, verification status and the reactions observed.

Anonymisation transforms data so that no individual can reasonably be identified, directly or indirectly, by anyone, after which the GDPR no longer applies to it.

ATC is the WHO classification of medicines by active substance, in five levels from the organ system (A, alimentary tract) down to the chemical substance (A10BA02, metformin).

ATNA is the IHE profile that requires every node in a health information exchange to authenticate itself with TLS certificates and to send a standard audit record for each access to patient data.

AuditEvent is the FHIR resource that logs a security-relevant action: who accessed or changed what, when, from where and with what outcome.

Binary is the FHIR resource that holds raw content of any media type, such as a PDF or a JPEG, either base64-encoded in JSON or returned as the file itself.

Break-the-glass is an emergency access mechanism: a clinician who is not normally permitted to see a record can override the restriction by declaring an emergency, with the access logged and reviewed afterwards.

Bulk Data export is the FHIR operation ($export) that lets an authorised client request all data for a population as NDJSON files, prepared asynchronously and downloaded when ready.

A Bundle is the FHIR container resource that groups several resources into one package, with a type that says why: searchset, document, transaction, batch, message, collection and others.

C-CDA is the US implementation guide that consolidates the most common CDA document templates (Continuity of Care Document, discharge summary, progress note) into one set.

CapabilityStatement is the FHIR resource a server publishes at /metadata to declare what it supports: FHIR version, resource types, search parameters, operations, security and implemented guides.

CDA is the HL7 XML standard for clinical documents such as discharge summaries, with a header (patient, author, date) and a body that can be free text or coded entries.

CDS Hooks is the HL7 specification by which an EHR calls an external decision-support service at defined moments (patient-view, order-select, order-sign) and shows the returned cards to the clinician.

A CodeableConcept is the FHIR datatype that represents one clinical concept with zero or more Codings (code plus code system) and an optional free-text display.

A Coding is the FHIR datatype for one code from one code system: the system URL, the code, an optional version and a display text.

Composition is the FHIR resource that gives a clinical document its structure: title, author, date, status and ordered sections, each pointing to the resources that are its content.

A ConceptMap is the FHIR resource that records how codes in one system map to codes in another, with the relationship (equivalent, wider, narrower) for each pair.

Condition is the FHIR resource for a diagnosis, problem or health concern, with a code (SNOMED CT and/or ICD-10), a clinical status (active, resolved) and a verification status (confirmed, provisional).

Consent is the FHIR resource that records a patient's permission or refusal: the scope (privacy, treatment, research), the actors allowed, the data classes, the purpose and the period.

De-identification is the US HIPAA term for removing identifiers from health data, by the Safe Harbor method (removing 18 listed identifiers) or by Expert Determination of very small re-identification risk.

DiagnosticReport is the FHIR resource that groups the results of a laboratory, pathology or imaging investigation: the ordered test, the issuing lab, the conclusion and references to the individual Observations.

DICOM is the standard for storing and transmitting medical images (CT, MRI, X-ray, ultrasound) together with their metadata, used by essentially every imaging device and archive.

DICOMweb is the family of RESTful web services defined in DICOM Part 18 for searching (QIDO-RS), retrieving (WADO-RS) and storing (STOW-RS) images over HTTP.

The DMP is France's shared medical record, the document store inside Mon espace santé, holding CDA documents (reports, prescriptions, the patient summary) that care professionals feed and read.

DocumentReference is the FHIR resource that indexes a document of any format (PDF, scan, CDA, image) with its type, date, author and a link to the content.

A DPIA is the assessment that GDPR Article 35 requires before high-risk processing: a description of the processing, its necessity, the risks to people and the measures that address them.

e-recepta is Poland's mandatory electronic prescription, issued through the P1 platform since 2020 and dispensed at any pharmacy with a four-digit code or from the IKP.

The EHDS is the EU regulation, in force since March 2025, that gives people the right to access and share their electronic health data across the EU (primary use) and sets a framework for research and policy use (secondary use).

An EHR is a patient's digital health record designed to be shared across organisations: the longitudinal history from several providers, not just one practice's chart.

eIDAS is the EU regulation on electronic identification and trust services (signatures, seals, timestamps), revised in 2024 to add the EU Digital Identity Wallet.

ELGA is Austria's national electronic health record, built on IHE XDS with CDA documents, that gives patients and treating providers access to discharge reports, lab and imaging results, e-Medikation and the e-Impfpass.

An EMR is the digital version of one provider's paper chart: the clinical record kept inside a single practice or hospital, under that organisation's control.

Encounter is the FHIR resource for an interaction between a patient and a provider: a visit, an admission, a telehealth call, with class, status, period, participants and diagnoses.

Endpoint is the FHIR resource that describes a technical address where a service can be reached: its URL, connection type (for example DICOMweb WADO-RS or a FHIR REST server) and payload types.

The ePA is Germany's electronic patient record, provided by the statutory health insurers and created for every insured person since January 2025 unless they opt out.

The EU ePrescription service lets a pharmacy in one member state retrieve and dispense a prescription issued electronically in another, through MyHealth@EU.

The EU AI Act is the regulation, in force since August 2024, that classifies AI systems by risk and sets obligations by class, with most of its rules applying from August 2026 and 2027.

$expand is the FHIR terminology operation that turns a value set definition into the explicit list of codes it contains, optionally filtered by a text search.

FHIR is the HL7 standard for exchanging health data as small, structured resources (Patient, Observation, Condition and about 150 more) over a REST API in JSON or XML.

A FHIR extension is the standard way to add an element the base resource does not have, identified by a URL that points to its definition, so that every system can at least recognise it.

A FHIR profile is a StructureDefinition that constrains a base resource for a use case: which elements are required, which value sets apply, which extensions are allowed.

FHIR R5 is the release published in March 2023, with topic-based subscriptions, new resources and many element changes compared with R4.

A FHIR resource is the basic unit of data in FHIR: a small JSON or XML document with a defined type (Patient, Observation, Condition) and known fields, identified by a URL.

FHIR search is the standard query interface: a GET on a resource type with parameters (patient, code, date, status), prefixes, modifiers, _include and paging, returning a searchset Bundle.

FHIRPath is the expression language for navigating and evaluating FHIR resources, such as Observation.value.ofType(Quantity).value > 7.

The FSE is Italy's electronic health record, run by the regions and linked nationally, which FSE 2.0 (from 2022) rebuilds around a national repository, CDA 2 documents and a FHIR gateway.

Article 9 of the GDPR prohibits processing health data unless one of its exceptions applies, most commonly explicit consent (9(2)(a)), provision of care (9(2)(h)) or public-interest research (9(2)(j)).

gematik is the German national agency for digital health, majority-owned by the federal health ministry, that specifies and certifies the Telematikinfrastruktur and its applications.

GP Connect is the NHS England service that lets authorised clinicians and systems access GP practice records (summary, structured medications and allergies, appointments) through FHIR APIs.

HCDSNS is Spain's national service that lets a clinician in one autonomous community view key documents from a patient's record held by another, since each community runs its own system.

Health Connect is the Android platform layer that stores health and fitness data on the device and lets apps read and write it with the user's per-data-type permission.

HealthKit is Apple's framework that stores health data on iPhone and Apple Watch and gives apps permission-based access to it, including clinical records downloaded from providers as FHIR.

HIPAA is the US federal law whose Privacy and Security Rules govern how covered entities (providers, insurers, clearinghouses) and their business associates handle protected health information.

A HIS is the hospital's central administrative and clinical system: patient registration, admissions, transfers, billing and usually the clinical record itself.

HL7 is the standards organisation, founded in 1987, that publishes HL7 v2, CDA and FHIR; the name refers to layer 7 (the application layer) of the OSI network model.

HL7 v2 is the pipe-delimited messaging standard, first published in 1989, that hospital systems still use to send admissions, orders and results to each other.

ICD-10 is the WHO classification of diseases and health problems, with alphanumeric codes such as E11 (type 2 diabetes), used worldwide for mortality statistics, reimbursement and reporting.

ICD-10-CM is the US clinical modification of ICD-10, with roughly 70,000 diagnosis codes up to seven characters long, maintained by the CDC and updated every October.

ICD-10-GM is the German modification of ICD-10, published yearly by BfArM and mandatory for diagnosis coding in German inpatient and outpatient care.

ICD-11 is the current WHO revision, in effect since January 2022, with a new code structure, post-coordination (combining codes) and a built-in API and browser.

An Identifier in FHIR is a business identifier made of a system (the namespace that issued it, as a URL or OID) and a value, such as a national health number or a hospital MRN.

IEC 62304 is the international standard for the life cycle of medical device software: planning, requirements, architecture, verification, release and maintenance, with safety classes A, B and C by the harm the software could cause.

IHE is an initiative that writes integration profiles: precise recipes for using existing standards (HL7, DICOM, FHIR) together to solve one clinical workflow, such as sharing documents between hospitals.

The IKP is Poland's online patient account, where a person sees their e-prescriptions, e-referrals, medical events, vaccinations and can grant access to a family member or a doctor.

ImagingStudy is the FHIR resource that describes a DICOM study (its UID, modality, series and instances) without containing the pixels.

Immunization is the FHIR resource that records one vaccine dose given (or not given, with the reason): the vaccine code, date, lot number, site, performer and dose number in the series.

An implementation guide is a published package of profiles, extensions, value sets, examples and narrative that says exactly how FHIR must be used in one context, such as a country or a programme.

The INS is France's national health identity: the person's national registration number plus the civil-status traits, verified against the national registry before use.

An interface engine is middleware that receives messages from one system, transforms them (HL7 v2 to FHIR, field mapping, filtering) and routes them to others, with queuing and logging.

Interoperability is the ability of different systems to exchange health data and to use what they receive without manual re-entry or custom translation.

The IPS is a standardised, minimal patient summary for unplanned, cross-border care: allergies, medications, problems, immunizations, procedures, results and devices, in a FHIR document.

ISO 13485 is the quality management system standard for organisations that design, produce or service medical devices, aligned with the MDR's QMS requirements.

ISO 27799 is the health-sector guideline that applies the ISO/IEC 27002 controls to personal health information, with specific requirements on access control, audit and record integrity.

ISO/IEC 27001 is the certifiable standard for an information security management system: risk assessment, a statement of applicability and the controls of Annex A.

The IVDR is the EU regulation for in vitro diagnostic devices, applicable since May 2022, covering tests performed on samples taken from the body and the software that interprets them.

A LIS is the laboratory's system that receives orders, tracks specimens, drives the analysers and releases results.

An LLM is a neural network trained on very large text corpora to predict and generate language, which is what powers assistants such as Claude and ChatGPT.

LOINC is the code system for laboratory tests and clinical measurements: each code (for example 2345-7, serum glucose) names what was measured, in which specimen, by which method.

$lookup is the FHIR terminology operation that, given a code and its system, returns the concept's display name, definition, designations and properties.

The LSP is the Dutch national switching point through which pharmacies, GPs and hospitals look up a patient's medication and summary data at other providers, with the patient's opt-in consent.

MCP is an open protocol that lets an AI assistant call external tools and read external data through a standard server interface, so the same connector works in Claude, ChatGPT and other clients.

The MDR is the EU regulation, fully applicable since May 2021, that governs medical devices including software, with classes I, IIa, IIb and III and CE marking requirements.

MedicationRequest is the FHIR resource for a prescription or medication order: the drug (coded), dosage instructions, the prescriber, the reason and dispensing details.

MedicationStatement is the FHIR resource that records that a patient is, was or will be taking a medication, as reported by the patient, a carer or a clinician, whether or not a prescription exists.

MedMij is the Dutch framework of standards and agreements under which a person's personal health environment (PGO) retrieves data from care providers' systems over FHIR.

MHD is the IHE profile that exposes an XDS document-sharing infrastructure through FHIR: DocumentReference for the index, Binary for the content and a FHIR List or Bundle for submission.

MLLP is the simple TCP framing used to send HL7 v2 messages: each message is wrapped in a start byte and an end byte sequence, and the receiver answers with an ACK.

Mon espace santé is France's national personal health space, opened for every insured person since 2022, that contains the DMP (the shared medical record), secure messaging, an agenda and a catalogue of approved apps.

An MPI is the index that assigns one enterprise identifier to a person and links all the local identifiers that different systems have given them.

MSH is the first segment of every HL7 v2 message: the delimiters, sending and receiving application and facility, timestamp, message type (for example ADT^A01), control ID and version.

MyHealth@EU is the EU infrastructure through which a patient summary or an ePrescription from one member state can be read by a pharmacist or doctor in another.

An NCPeH is the gateway each EU country operates for MyHealth@EU: it translates the national record into the European format and exchanges it with other countries' contact points.

The NHS Spine is the central infrastructure of the English NHS that holds the Personal Demographics Service (the NHS number index), the Summary Care Record and the messaging services between systems.

NIS2 is the EU cybersecurity directive, transposed into national law from October 2024, that makes healthcare providers and some health-tech suppliers "essential" or "important" entities with risk-management and incident-reporting duties.

OAuth 2.1 is the consolidated revision of the OAuth 2.0 authorisation framework that makes PKCE mandatory, removes the implicit and password grants and requires exact redirect URI matching.

OBR is the HL7 v2 segment that describes one ordered test or panel: the order numbers, the universal service identifier (what was ordered), the observation time and the result status.

Observation is the FHIR resource for a single measurement or finding: a lab result, a vital sign, a symptom score, with a code (usually LOINC), a value and unit (UCUM), a time and a status.

OBX is the HL7 v2 segment that carries one result value: the value type (OBX-2), the observation identifier (OBX-3, ideally a LOINC code), the value (OBX-5), the unit (OBX-6), the reference range and the abnormal flag.

OML^O21 is the HL7 v2.5+ laboratory order message that replaced ORM for lab use, with specimen (SPM) and container details that ORM lacked.

The OMOP CDM is a standardised relational schema, maintained by the OHDSI community, into which health data from any source is converted so that the same analysis can run on every converted database.

openEHR is an open specification for storing a lifelong electronic health record, built on a stable reference model plus clinician-authored archetypes and templates that define the clinical content.

OpenID Connect is the identity layer on top of OAuth 2.0: it adds an ID token (a signed JWT) that tells the app who the user is, with standard claims and a discovery document.

OperationOutcome is the FHIR resource a server returns to explain errors, warnings or information about a request, with a severity, a code and a human-readable diagnostic for each issue.

ORC is the HL7 v2 segment with the order control information shared by all order types: order control code (new, cancel), placer and filler order numbers, status, timing and the ordering provider.

Organization is the FHIR resource for a hospital, clinic, laboratory, insurer or department, with identifiers, type, name, contact details and a reference to a parent organisation.

ORM^O01 is the classic HL7 v2 order message (version 2.3 to 2.5) with which a clinical system asks a lab, radiology or pharmacy to perform something, built around ORC and OBR segments.

ORU^R01 is the HL7 v2 message that carries results: one OBR segment per ordered test and one OBX segment per value, from a laboratory, a radiology system or a device.

P1 is Poland's national e-health platform, run by the Centrum e-Zdrowia, that processes e-prescriptions, e-referrals and the exchange of medical event records between providers.

A PACS is the system that stores and displays medical images in DICOM format and delivers them to radiologists and clinicians for reading.

Patient is the FHIR resource that holds who a person is: identifiers, names, birth date, administrative gender, contact details and links to related records.

Patient matching is the process of deciding whether two records from different systems belong to the same person, by comparing demographics (name, birth date, sex, address) deterministically or probabilistically.

A PHR is a health record that the patient keeps and controls, combining data from clinics, labs, devices and their own notes in one place they can share.

PID is the HL7 v2 segment that identifies the patient: identifiers (PID-3), name (PID-5), date of birth (PID-7), sex (PID-8), address and contact details.

PIX and PDQ are the IHE profiles for patient identity: PIX cross-references a patient's identifiers across systems, and PDQ lets a system search for a patient by demographics.

PKCE is the OAuth extension in which the client sends a hashed secret with the authorisation request and the original with the token request, so an intercepted code cannot be redeemed by anyone else.

Practitioner is the FHIR resource for a person involved in care: a doctor, nurse, pharmacist or technician, with identifiers (licence numbers), name, qualifications and contact details.

Provenance is the record of where a piece of data came from, who produced it, when and from what, so that a reader can judge how much to trust it.

Provenance is the FHIR resource that records where another resource came from: who created or changed it, when, on behalf of whom, from which source and by which activity.

Pseudonymisation replaces direct identifiers with a key or token so that the data can no longer be attributed to a person without additional information that is kept separately.

A QHIN is a network that has been designated under TEFCA to connect participants (hospitals, vendors, payers) to the other QHINs, so that a query reaches every connected organisation in the US.

QIDO-RS is the DICOMweb search service: a GET on /studies, /series or /instances with query parameters (patient ID, date, modality) returns matching metadata as JSON or XML.

RAG is the pattern in which a language model is given retrieved documents or records relevant to the question before it answers, instead of relying on what it learned in training.

Real-world data is health data collected outside clinical trials, from records, registries, claims and devices, and real-world evidence is what is derived from analysing it.

A RIS is the radiology department's workflow system: scheduling, orders, worklists for the scanners, dictation and the final report.

RxNorm is the US National Library of Medicine's code system for clinical drugs, with a normalised name and code for each ingredient, strength and dose form (for example "metformin 500 mg oral tablet").

SaMD is software that is itself a medical device: it has a medical purpose (diagnosis, treatment, monitoring) and runs on general hardware rather than being part of a device.

Secondary use is the use of health data for purposes other than the care it was collected for: research, statistics, policy, product development, and under the EHDS the training of AI.

ServiceRequest is the FHIR resource for an order or referral: a lab test, an imaging study, a procedure or a consultation that someone asks to be done.

A SMART Health Card is a signed, compact FHIR Bundle (typically immunizations or lab results) packed into a QR code that a verifier can check without contacting the issuer.

A SMART Health Link is a URL or QR code that shares encrypted health data (for example an IPS) with whoever holds the link, optionally protected by a passcode and limited in time.

SMART on FHIR is the HL7 specification for how an app gets authorised to read a FHIR server, using OAuth 2.0 with scopes such as patient/Observation.read and a launch context (which patient, which encounter).

SNOMED CT is the largest clinical terminology, with over 350,000 concepts for findings, disorders, procedures, body structures and more, arranged in a hierarchy that software can reason over.

Specimen is the FHIR resource for the sample a laboratory tests: its type (blood, urine, tissue), collection time and method, container and condition on arrival.

STOW-RS is the DICOMweb store service: a POST of DICOM instances (or metadata plus bulk data) to /studies writes them into an archive.

Subscription is the FHIR resource with which a client asks a server to notify it (by REST hook, websocket or email) whenever resources matching its criteria are created or updated.

SubscriptionTopic is the R5 (and R4B backport) resource in which a server publishes the events clients can subscribe to, such as "new lab result for a patient", with the triggers and the payload shape.

Synthetic health data is artificially generated data that mimics the statistics and structure of real records without describing any real person.

TEFCA is the US framework, live since December 2023, under which designated networks (QHINs) exchange health data nationwide under one common legal agreement and technical rules.

The Telematikinfrastruktur is Germany's closed, secure network that connects practices, hospitals, pharmacies and insurers to the national e-health services (ePA, e-prescription, e-sick note).

A terminology server is a FHIR server that hosts code systems, value sets and concept maps and answers questions about them through operations such as $lookup, $validate-code, $expand and $translate.

$translate is the FHIR terminology operation that maps a code from one system to the matching code in another, using one or more ConceptMaps on the server.

UCUM is the code system for units of measure in which every unit has one unambiguous, machine-readable form, such as mg/dL, mmol/L or 10*3/uL.

US Core is the HL7 implementation guide that profiles FHIR R4 for the United States, defining how each USCDI data class is represented and which codes it must use.

USCDI is the ONC-defined list of data classes and elements (allergies, medications, lab results, notes) that certified US health IT must be able to exchange, updated in yearly versions.

A ValueSet is the FHIR resource that defines which codes, from one or more code systems, are allowed in a given element, for example the set of SNOMED CT codes a profile accepts for an allergy.

A VNA is a long-term image archive that stores DICOM (and often non-DICOM) objects in a standard way so that any PACS or viewer, from any vendor, can read them.

WADO-RS is the DICOMweb retrieve service: a GET request on a study, series or instance URL returns the DICOM objects, their metadata or rendered images.

XCA is the IHE profile that lets one XDS community query and retrieve documents from another, through gateways on each side.

XDS is the IHE profile for sharing clinical documents within a community: a registry indexes the documents and one or more repositories store them.