Hello!
The answer to this question gets a little complicated with the breadth of Cerner solutions available to our clients. I will attempt to provide some insights to try and help.
Cerner Millennium is a patient-centric platform that houses a multitude of end-user solutions. The platform is built on top of a single data store designed with the "single patient, single record" goal in mind. Ignite APIs for Millennium is a solution that exposes this patient-centric data model to third party users. So, if we provide an API such as Observation, that API will serve up the data set created by any end user solutions that are part of Millennium platform. In other words, from the point of interaction with the data set, it does not matter which particular Millennium solution produced that data set.
There is a different aspect to this platform when it comes to SMART app integration. In order for a third party to integrate their solution into end-user workflow, we have to create an access point within a particular Cerner solution to allow launch of a SMART app. Currently we support four access points [1] as well as standalone app launch. We expect to grow the number of access over time. In part the number of access points available is driven by the type of FHIR APIs we support and in part it is driven by developer demand. For example, as we build more FHIR resources that serve up datasets that align with Revenue Cycle use cases, we will likely see a new set of developers wanting to integrate into our Revenue Cycle solutions and will likely add new access points there.
Thanks,
Yegor (Cerner)