What is C3-PRO?

C3-PRO is a set of FHIR® compliant software tools and systems that enables integration of biomedical research data collected via ResearchKit and ResearchStack into i2b2 and other databases in a secure, highly scalable fashion.

For Developers

Source code for all our modules is available on GitHub. We've set up a Google Group for discussions and updates, feel free to stop by and ask questions.

» Google Group


The ecosystem supporting mobile research is expanding, and the list of modules that plug in to C3-PRO is growing. See the architecture overview below to find software modules that suit your needs.


The C3-PRO toolchain is made up of various software modules living in three areas: embedded into your mobile app, server-side pieces that live openly on the www, and modules living behind a firewall, with access to your backend.

Since data exchange happens via FHIR Resources (or encrypted versions thereof), you can easily substitute each component with your own solution. You may also just use parts of the toolchain. Our mobile frameworks for example greatly simplify working with ResearchKit and ResearchStack.

C3-PRO Architecture Diagram

The diagram above illustrates the traditional data flow in a C3-PRO environment. On the mobile side, the iOS and Android mobile frameworks facilitate working with ResearchKit and ResearchStack, respectively, sending encrypted data to (and retrieving data from) the receiver server living on the open web. Secure systems, capable of decrypting incoming data, are running behind the institution’s firewall and store data into an i2b2 research backend.

From the list below you can pick the modules that best suit your needs to design a custom data flow.


C3-PRO Android Framework

by MHC, University Hospital Zurich

This framework uses the HAPI 🔥FHIR library and ResearchStack to bring C3-PRO to Android.

Android Android ResearchStack ResearchStack Java Java

C3-PRO iOS Framework

by CHIP, Boston Children’s Hospital

This iOS framework allows you to use 🔥FHIR resources directly with ResearchKit.

iOS iOS ResearchKit ResearchKit Swift Swift OAuth2 OAuth2 Encryption Encryption


C3-PRO “Receiver” Server

by CHIP, Boston Children’s Hospital

Serves as point-of-contact with the app and is the only public-facing part of the toolchain.

OAuth2 OAuth2 AWS AWS JBoss JBoss Java Java


C3-PRO “Consumer”

by CHIP, Boston Children’s Hospital

Daemon that runs in-house, consumes from the “receiver”'s SQS queue and decrypts 🔥FHIR resources.

AWS AWS JBoss JBoss Java Java Encryption Encryption

i2b2 FHIR Cell

by CHIP, Boston Children’s Hospital

A 🔥FHIR DSTU-2 compliant cell for i2b2.

i2b2 i2b2 JBoss JBoss Java Java

Open Source, Open Access

All our C3-PRO modules are available open source, Apache 2 licensed.

Presentations, publications, print and online materials should cite the C3-PRO PLoS ONE publication as shown belowto the right. To acknowledge the use of C3-PRO in your software, please refer to the NOTICE file in the software repositories that you use.
					Pfiffner PB, Pinyol I, Natter MD, Mandl KD (2016) C3-PRO: Connecting ResearchKit to the Health System Using i2b2 and FHIR. PLoS ONE 11(3): e0152722. doi:10.1371/journal.pone.0152722.