synthea

SyntheaTM Patient Generator

SyntheaTM is a Synthetic Patient Population Simulator. The goal is to output synthetic, realistic (but not real), patient data and associated health records in a variety of formats.

Read our wiki and Frequently Asked Questions for more information.

Currently, SyntheaTM features include:

• Birth to Death Lifecycle
• Configuration-based statistics and demographics (defaults with Massachusetts Census data)
• Modular Rule System
  • Drop in Generic Modules
  • Custom Java rules modules for additional capabilities
• Primary Care Encounters, Emergency Room Encounters, and Symptom-Driven Encounters
• Conditions, Allergies, Medications, Vaccinations, Observations/Vitals, Labs, Procedures, CarePlans
• Formats
  • HL7 FHIR (R4, STU3 v3.0.1, and DSTU2 v1.0.2)
  • Bulk FHIR in ndjson format (set exporter.fhir.bulk_data = true to activate)
  • C-CDA (set exporter.ccda.export = true to activate)
  • CSV (set exporter.csv.export = true to activate)
  • CPCDS (set exporter.cpcds.export = true to activate)
• Rendering Rules and Disease Modules with Graphviz

Developer Quick Start

These instructions are intended for those wishing to examine the Synthea source code, extend it or build the code locally. Those just wishing to run Synthea should follow the Basic Setup and Running instructions instead.

Installation

System Requirements: SyntheaTM requires Java JDK 17 or newer. We strongly recommend using a Long-Term Support (LTS) release of Java, 17 or 25, as issues may occur with more recent non-LTS versions.

To clone the SyntheaTM repo, then build and run the test suite:

git clone https://github.com/synthetichealth/synthea.git
cd synthea
./gradlew build check test

Changing the default properties

The default properties file values can be found at src/main/resources/synthea.properties. By default, synthea does not generate CCDA, CPCDA, CSV, or Bulk FHIR (ndjson). You'll need to adjust this file to activate these features. See the wiki for more details, or use our guided customizer tool.

Generate Synthetic Patients

Generating the population one at a time...

./run_synthea

Command-line arguments may be provided to specify a state, city, population size, or seed for randomization.

run_synthea [-s seed] [-p populationSize] [state [city]]

Full usage info can be printed by passing the -h option.

…

Some settings can be changed in ./src/main/resources/synthea.properties.

SyntheaTM will output patient records in C-CDA and FHIR formats in ./output.

SyntheaTM GraphViz

Generate graphical visualizations of SyntheaTM rules and modules.

./gradlew graphviz

Concepts and Attributes

Generate a list of concepts (used in the records) or attributes (variables on each patient).

./gradlew concepts
./gradlew attributes

License

Copyright 2017-2025 The MITRE Corporation

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.