Search for the "functional components of an EHR" and you will find lists of five, six, eight or more, often with no source. The different counts come from different frameworks, each written for a different purpose. Knowing which one you are looking at makes it easier to compare systems.
This guide is for practice owners, administrators and physicians evaluating an electronic health record (EHR). It explains the three frameworks most often cited, what each says an EHR should do, and how to turn them into practical questions for a vendor demo. For the separate question of what kinds of systems exist, see our guide to types of EMR systems.
What are the functional components of an EHR?
There is no single official list of five. The most widely cited source is a 2003 Institute of Medicine report that named eight core functions. The current federal Base EHR definition lists five capabilities a certified system must have. HL7's EHR System Functional Model organizes functions into seven sections. Each is accurate for its purpose.
All three describe the same basic job. HealthIT.gov describes an EHR as a digital version of a patient's chart, kept over time, that authorized users can access, with tools that support decisions about care and help automate the provider's workflow. The frameworks break that job into parts in different ways.
What are the eight core functions from the Institute of Medicine?
In 2003, the Department of Health and Human Services asked the Institute of Medicine (IOM) for guidance on the key care delivery capabilities of an EHR system. Its letter report, Key Capabilities of an Electronic Health Record System, grouped core functions into eight categories.
| IOM core function | What it covers, in plain terms |
|---|---|
| Health information and data | The patient data clinicians need at the point of care: diagnoses, medications, allergies, demographics, notes and test results. |
| Results management | Receiving and displaying lab and imaging results, including earlier results for comparison. |
| Order entry and management | Entering orders for tests, prescriptions and services electronically. |
| Decision support | Reminders, alerts and prompts that help with prevention, prescribing and diagnosis. |
| Electronic communication and connectivity | Communication among the care team, with outside partners such as labs and pharmacies, and with patients. |
| Patient support | Tools such as patient education and home monitoring. |
| Administrative processes | Scheduling of appointments and procedures, insurance eligibility checks and similar administrative tasks. |
| Reporting and population health | Required reporting on patient safety, quality and public health, and internal quality tracking. |
The report also noted that HL7, a health data standards organization, planned to build these functions into its EHR functional model. That is how the IOM list became the starting point for later frameworks.
What does the federal Base EHR definition require?
The Base EHR definition, published by the Office of the National Coordinator for Health IT (ONC), sets the minimum capabilities certified health IT must have. It currently lists five: patient demographic and clinical information, clinical decision support, physician order entry, capturing and querying quality information, and exchanging health information with other sources.
ONC's page also lists real-time prescription benefit information, required from January 1, 2028. The Base EHR definition is the baseline for certified EHR technology (CEHRT), which the Centers for Medicare & Medicaid Services (CMS) requires for certain programs. If your practice participates in one of those programs, confirm the current requirements for your program and reporting year.
If you have seen a list of "five functional components" elsewhere, this is the closest official list of five. Note that it is a certification baseline, not a description of everything a working practice needs.
How does the HL7 EHR System Functional Model organize functions?
HL7's EHR System Functional Model (EHR-S FM), Release 2.1.1, is a standard that sorts EHR functions into seven sections. Vendors and specialty groups use it to describe what a system does in a consistent way and to build profiles for particular care settings.
- Overarching: criteria that apply to every EHR system.
- Care Provision: functions for direct, hands-on care of a specific patient.
- Care Provision Support: functions that support that care, organized to match Care Provision.
- Population Health Support: functions for disease prevention and control across groups of patients.
- Administration Support: management of the practice, including administrative and financial operations.
- Record Infrastructure: managing the record over its lifecycle, from creation and amendment to access and disclosure.
- Trust Infrastructure: security, privacy, data integrity and system operations.
