Data Engineering & Interoperability Glossary
Definitions for essential terms in data engineering, interoperability standards, and systems integration.
A
- ADT — Admission, Discharge, Transfer
- HL7 message type used to communicate patient movement events within or between healthcare facilities. ADT^A01 = Admit, ADT^A03 = Discharge, ADT^A08 = Update.
C
- C-CDA — Consolidated Clinical Document Architecture
- An HL7 standard for structuring clinical documents as XML. Used for care summaries, discharge documents, and referral notes. Contains both human-readable narrative and machine-readable structured data.
D
- DICOM — Digital Imaging and Communications in Medicine
- The standard for medical imaging files (X-rays, MRIs, CT scans). Defines file format and network protocols for transmitting imaging data.
- DRG — Diagnosis-Related Group
- A patient classification system that standardizes hospital reimbursement. CMS assigns each inpatient stay a DRG code based on diagnosis, procedures, and patient characteristics.
E
- EDI — Electronic Data Interchange
- Machine-to-machine electronic exchange of structured business documents. In healthcare, EDI 837 is the standard claims transaction, 835 is the remittance advice.
- EHR — Electronic Health Record
- A digital version of a patient's medical record maintained by a healthcare provider. Major US EHR vendors include Epic, Cerner, Meditech, and Allscripts.
- ELT — Extract, Load, Transform
- A data pipeline pattern where raw data is first loaded into a storage system, then transformed in-place. Commonly evaluated for cloud data lakes where compute is elastic.
- ETL — Extract, Transform, Load
- A data pipeline pattern where data is extracted from sources, transformed to match the target schema, then loaded into the destination. Traditional approach for relational data warehouses.
F
- FHIR — Fast Healthcare Interoperability Resources
- The HL7 standard for RESTful healthcare data APIs using JSON or XML. FHIR R4 is mandated by the US 21st Century Cures Act for EHR vendor APIs and payer data exchange.
H
- HL7 — Health Level Seven
- An international standards organization (and the standards it produces) for healthcare information exchange. HL7 v2 is the most deployed messaging standard; FHIR is its modern successor.
I
- ICD-10 — International Classification of Diseases, 10th Revision
- The standard coding system for diagnoses and procedures used in US healthcare billing, public health reporting, and clinical documentation.
L
- LOINC — Logical Observation Identifiers Names and Codes
- A universal standard for identifying laboratory and clinical observations. Every lab test, vital sign, and survey question has a LOINC code. Required in FHIR Observation resources.
M
- MLLP — Minimal Lower Layer Protocol
- The transport protocol used to send HL7 v2 messages over TCP/IP. MLLP wraps HL7 messages with start-of-block (0x0B) and end-of-block (0x1C 0x0D) characters.
- MRN — Medical Record Number
- A unique identifier assigned to each patient by a healthcare facility. Maps to HL7 PID-3. Different from national identifiers like SSN or insurance member IDs.
N
- NDC — National Drug Code
- A unique identifier for human drugs in the United States, assigned by the FDA. Used in medication orders, pharmacy dispensing, and claims.
- NPI — National Provider Identifier
- A 10-digit unique identification number for healthcare providers in the US. Assigned by CMS and used in all HIPAA transactions.
O
- ORU — Observation Result Unsolicited
- An HL7 message type that carries clinical results (lab, vitals, observations) from a source system (LIS, device) to a receiving system. ORU^R01 is the most common.
P
- PHI — Protected Health Information
- Any individually identifiable health information covered by HIPAA. Includes patient names, dates, geographic data, contact information, and health record numbers. Must be protected in transit and at rest.
R
- RxNorm — RxNorm
- A normalized naming system for clinical drugs maintained by the NLM. Provides standardized names and identifiers for medications. Required in FHIR MedicationRequest resources.
S
- SMART on FHIR — Substitutable Medical Applications, Reusable Technologies
- An open standard for healthcare application authorization and launch. Allows third-party apps to securely access patient data from FHIR servers using OAuth 2.0.
- SNOMED CT — Systematized Nomenclature of Medicine Clinical Terms
- A comprehensive clinical terminology system used globally for clinical documentation. Used in FHIR Condition, Procedure, and Observation resources for diagnosis and finding codes.