FHIR protocol questions

Question

We are a HISP connecting doctors and patients looking at adopting FHIR protocol. I have few questions regarding FHIR.

1. We are looking at serializing FHIR resources as JSON in Couchbase. Is serializing FHR resources as-is a right approach?

2. How can I add new resources in addition to already defined ones? I read about creating "Other" resource and define all properties as extensions. Is it the right approach?

3. How can I define value sets like medication code, gender etc or any kind of lookup as a resource?

4. I see "Contained" resource as a way to add a reference. In some scenarios it can be expensive to send many references. Is it possible to define a resource that has "Contained" resource but has actual value instead of reference? Here is an example: I'm an intermediary site where patients can book appointments and I send the data to a practice's EHR. I'd like to send full patient resource instead of display name alone (see example below). How do I do this?

   Part of appointment resource sample:

   "participant":[{"individual":{"reference":"Patient/example","display":"Peter James Chalmers"},"required":"required","status":"accepted"},{"type":[{"coding":[{"code":"attending"}]}]

5. How are resources defined in FHIR correspond to C-CDA? For example, if a C-CDA document comes from a EHR, how can I transform to a FHIR resource? If an EHR consumes only C-CDA, how can I convert FHIR resource to C-CDA before sending to EHR.

6. Are there push notification mechanism built in FHIR? For example, I may want to push record changes to a patient's iPhone or push changes to an EHR.

7. Are there open source .Net libraries for FHIR that can help us jump start?

8. What is the recommended way to do authentication & authorization? I'd like to use oAuth2.

Thanks.

Answer 1

1 . We are looking at serializing FHIR resources as JSON in Couchbase. Is serializing FHR resources as-is a right approach?

it's "a" right approach, yes. There are others

2 . How can I add new resources in addition to already defined ones? I read about creating "Other" resource and define all properties as extensions. Is it the right approach?

Yes, for now; in principle it is intended to be possible to define real additional resources, but what the rules will be are not yet defined

3 . How can I define value sets like medication code, gender etc or any kind of lookup as a resource?

using the value set resource.

4 . I see "Contained" resource as a way to add a reference. In some scenarios it can be expensive to send many references. Is it possible to define a resource that has "Contained" resource but has actual value instead of reference?

I don't know what you mean.

5 . How are resources defined in FHIR correspond to C-CDA? For example, if a C-CDA document comes from a EHR, how can I transform to a FHIR resource? If an EHR consumes only C-CDA, how can I convert FHIR resource to C-CDA before sending to EHR.

Roughly, an section corresponds to the List resource, and an entry to a resource. There's no formal published work on alignment between C-CDA and FHIR yet, though some operational work exists here:

6 . Are there push notification mechanism built in FHIR? For example, I may want to push record changes to a patient's iPhone or push changes to an EHR.

Well, in the EHR case, the EHR should offer a FHIR server, and you create/update on the EHR. For a mobile client, the rules are different. You can't just push stuff at a phone, you need some kind of client initiation. We have added Subscriptions to the development version of FHIR (see the continuous build), but these are not in the DSTU version

7 . Are there open source .Net libraries for FHIR that can help us jump start?"

yes. see http://hl7.org/fhir/downloads.html

8 . What is the recommended way to do authentication & authorization? I'd like to use oAuth2.

We recommend OAuth