As we build a NIEM/FHIR bridge I think we need to delve a little more into the non-technical processes that needs to be undertaken to achieve this bridge (in plain English). We typically jump into technical considerations, making assertions about how interoperability will be achieved with specific protocols, without first clearly laying out the underlying concept, roles, governance, and process involved.

-How will a human services data element be identified/selected for inclusion?

-What about data flows, such as case management, that don't always involve health care? We could build upon recent Care Plan work to have a general human services case management structure added to NIEM, for the purposes of InCK.

-What will be the process for mapping equivalencies to health data elements?

-Will someone need to maintain those mappings? NIEM Health could be a great place for that, but XML schema isn't nimble enough for mappings like that. Plus, most human services don't use NIEM. So maybe NIEM Health could look a little different than other NIEM domains., and first start with being a web vocabulary (https://www.w3.org/OWL/) to map everything flexibly?   NIEM is moving in this direction with JSON-LD (JSON that is semantically aware, by referencing vocabularies. I think eventually, NIEM should move to being a web vocabulary, onward and upward from being a very limiting XML Schema).

Maybe we need to create a NIC repository (git?) of human services to NIEM vocabulary mappings, so we don't have to wait for official agency NIEM adoption to get the bridge built.

Of course, this could all be done in a prioritized, incremental fashion, so we're not boiling the ocean.

Start maybe with any human services field. Map its logical model to NIEM Core. We won't be inventing any new elements here; just mapping from existing standards.  Then try sending the mapped elements to healthcare systems using FHIR, filtering further through the NIEM Health mappings.