Interoperability with the CHT

In this forum post, I will provide an overview of the tools and standards used to create an interoperability layer in the CHT.

Under the Hood: an overview of the standards and technologies used

Fast Healthcare Interoperability Resources

FHIR (Fast Healthcare Interoperability Resources) is a standard for exchanging healthcare data electronically. FHIR provides a modern, web-based approach to exchanging healthcare data, rapidly becoming the preferred standard for healthcare interoperability.


OpenHIE is an open-source framework for building interoperable health information systems. OpenHIE provides a set of standards and protocols for enabling different health systems and applications to communicate with each other.


OpenHIM is an open-source middleware platform that provides a central point of control for managing health information exchange (HIE). OpenHIM enables healthcare providers to connect different health systems and applications, and provides a common interface for managing data exchange and security.

Creating an Interoperability Layer for the Community Health Toolkit (CHT)

Work on exploring possible use cases for interoperability between Community Health Information Systems like the CHT started in early 2022 by a technical working group composed of members from Medic and Ona, LG and Dimagi. This group identified one type of use case that was a good start for testing interoperability: the Request Community Based Follow Up.

In the context of this Proof of Concept, we use OpenHIM to provide a central point of control for managing data exchange and security. OpenHIM enables us to monitor and manage data exchange between the CHT and other health systems and applications. We also leverage OpenHIM to implement security measures, such as authentication and authorization, to ensure that data is exchanged securely.

We created a mediator in charge of ensuring data is formatted in a way that can be understood by FHIR-compliant systems and the CHT, which is not natively FHIR compliant. A publicly available repository was created for this work. All the services can be run via Docker, making both local and production deployments relatively easy.

A sequence diagram of the workflow as is currently implemented is shown below.

Currently, we make use of the Patient, Encounter, and Subscription FHIR resources with work in progress to make the “Loss To Follow Up Patient” request a Service Request.


In conclusion, interoperability is critical for improving healthcare delivery and patient outcomes. By enabling different health systems and applications to communicate with each other, interoperability can improve care coordination, reduce medical errors, and increase the efficiency of healthcare delivery.

The loss to follow up workflow described above was successfully reproduced using the CHT. Documentation on this work can be found in this repository which anyone can run as long as they have docker installed.

At Medic, we are committed to improving healthcare delivery through the use of technology. By leveraging OpenHIM, OpenHIE, and FHIR, we have created an interoperability layer in the CHT that enables healthcare providers to provide more comprehensive care.


Thank you @njuguna for this article
It’s enlightening


Thanks, this is helpful.